Rebase to latest 9.0

9 files changed, 8448 insertions, 1205 deletions

diff --git a/generic/tclClock.c b/generic/tclClock.c
index b870f79..6c6ac94 100644
--- a/generic/tclClock.c
+++ b/generic/tclClock.c
@@ -8,6 +8,7 @@
  * Copyright © 1991-1995 Karl Lehenbauer & Mark Diekhans.
  * Copyright © 1995 Sun Microsystems, Inc.
  * Copyright © 2004 Kevin B. Kenny. All rights reserved.
+ * Copyright © 2015 Sergey G. Brester aka sebres. All rights reserved.
  *
  * See the file "license.terms" for information on usage and redistribution of
  * this file, and for a DISCLAIMER OF ALL WARRANTIES.
@@ -15,6 +16,8 @@
 
 #include "tclInt.h"
 #include "tclTomMath.h"
+#include "tclStrIdxTree.h"
+#include "tclDate.h"
 
 /*
  * Windows has mktime. The configurators do not check.
@@ -25,24 +28,13 @@
 #endif
 
 /*
- * Constants
- */
-
-#define JULIAN_DAY_POSIX_EPOCH		2440588
-#define SECONDS_PER_DAY			86400
-#define JULIAN_SEC_POSIX_EPOCH	      (((Tcl_WideInt) JULIAN_DAY_POSIX_EPOCH) \
-					* SECONDS_PER_DAY)
-#define FOUR_CENTURIES			146097	/* days */
-#define JDAY_1_JAN_1_CE_JULIAN		1721424
-#define JDAY_1_JAN_1_CE_GREGORIAN	1721426
-#define ONE_CENTURY_GREGORIAN		36524	/* days */
-#define FOUR_YEARS			1461	/* days */
-#define ONE_YEAR			365	/* days */
-
-/*
  * Table of the days in each month, leap and common years
  */
 
+static const int hath[2][12] = {
+    {31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31},
+    {31, 29, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31}
+};
 static const int daysInPriorMonths[2][13] = {
     {0, 31, 59, 90, 120, 151, 181, 212, 243, 273, 304, 334, 365},
     {0, 31, 60, 91, 121, 152, 182, 213, 244, 274, 305, 335, 366}
@@ -52,70 +44,13 @@ static const int daysInPriorMonths[2][13] = {
  * Enumeration of the string literals used in [clock]
  */
 
-typedef enum ClockLiteral {
-    LIT__NIL,
-    LIT__DEFAULT_FORMAT,
-    LIT_BCE,		LIT_C,
-    LIT_CANNOT_USE_GMT_AND_TIMEZONE,
-    LIT_CE,
-    LIT_DAYOFMONTH,	LIT_DAYOFWEEK,		LIT_DAYOFYEAR,
-    LIT_ERA,		LIT_GMT,		LIT_GREGORIAN,
-    LIT_INTEGER_VALUE_TOO_LARGE,
-    LIT_ISO8601WEEK,	LIT_ISO8601YEAR,
-    LIT_JULIANDAY,	LIT_LOCALSECONDS,
-    LIT_MONTH,
-    LIT_SECONDS,	LIT_TZNAME,		LIT_TZOFFSET,
-    LIT_YEAR,
-    LIT__END
-} ClockLiteral;
-static const char *const literals[] = {
-    "",
-    "%a %b %d %H:%M:%S %Z %Y",
-    "BCE",		"C",
-    "cannot use -gmt and -timezone in same call",
-    "CE",
-    "dayOfMonth",	"dayOfWeek",		"dayOfYear",
-    "era",		":GMT",			"gregorian",
-    "integer value too large to represent",
-    "iso8601Week",	"iso8601Year",
-    "julianDay",	"localSeconds",
-    "month",
-    "seconds",		"tzName",		"tzOffset",
-    "year"
-};
+CLOCK_LITERAL_ARRAY(Literals);
 
-/*
- * Structure containing the client data for [clock]
- */
+/* Msgcat literals for exact match (mcKey) */
+CLOCK_LOCALE_LITERAL_ARRAY(MsgCtLiterals, "");
+/* Msgcat index literals prefixed with _IDX_, used for quick dictionary search */
+CLOCK_LOCALE_LITERAL_ARRAY(MsgCtLitIdxs, "_IDX_");
 
-typedef struct {
-    size_t refCount;		/* Number of live references. */
-    Tcl_Obj **literals;		/* Pool of object literals. */
-} ClockClientData;
-
-/*
- * Structure containing the fields used in [clock format] and [clock scan]
- */
-
-typedef struct {
-    Tcl_WideInt seconds;	/* Time expressed in seconds from the Posix
-				 * epoch */
-    Tcl_WideInt localSeconds;	/* Local time expressed in nominal seconds
-				 * from the Posix epoch */
-    int tzOffset;		/* Time zone offset in seconds east of
-				 * Greenwich */
-    Tcl_Obj *tzName;		/* Time zone name */
-    int julianDay;		/* Julian Day Number in local time zone */
-    int isBce;			/* 1 if BCE */
-    int gregorian;		/* Flag == 1 if the date is Gregorian */
-    int year;			/* Year of the era */
-    int dayOfYear;		/* Day of the year (1 January == 1) */
-    int month;			/* Month number */
-    int dayOfMonth;		/* Day of the month */
-    int iso8601Year;		/* ISO8601 week-based year */
-    int iso8601Week;		/* ISO8601 week number */
-    int dayOfWeek;		/* Day of the week */
-} TclDateFields;
 static const char *const eras[] = { "CE", "BCE", NULL };
 
 /*
@@ -136,41 +71,56 @@ TCL_DECLARE_MUTEX(clockMutex)
  * Function prototypes for local procedures in this file:
  */
 
-static int		ConvertUTCToLocal(Tcl_Interp *,
-			    TclDateFields *, Tcl_Obj *, int);
 static int		ConvertUTCToLocalUsingTable(Tcl_Interp *,
-			    TclDateFields *, Tcl_Size, Tcl_Obj *const[]);
+			    TclDateFields *, Tcl_Size, Tcl_Obj *const[],
+			    Tcl_WideInt *rangesVal);
 static int		ConvertUTCToLocalUsingC(Tcl_Interp *,
 			    TclDateFields *, int);
-static int		ConvertLocalToUTC(Tcl_Interp *,
-			    TclDateFields *, Tcl_Obj *, int);
+static int		ConvertLocalToUTC(void *clientData, Tcl_Interp *,
+			    TclDateFields *, Tcl_Obj *timezoneObj, int);
 static int		ConvertLocalToUTCUsingTable(Tcl_Interp *,
-			    TclDateFields *, Tcl_Size, Tcl_Obj *const[]);
+			    TclDateFields *, int, Tcl_Obj *const[],
+			    Tcl_WideInt *rangesVal);
 static int		ConvertLocalToUTCUsingC(Tcl_Interp *,
 			    TclDateFields *, int);
-static Tcl_Obj *	LookupLastTransition(Tcl_Interp *, Tcl_WideInt,
-			    Tcl_Size, Tcl_Obj *const *);
+static int		ClockConfigureObjCmd(void *clientData,
+			    Tcl_Interp *interp, int objc, Tcl_Obj *const objv[]);
 static void		GetYearWeekDay(TclDateFields *, int);
 static void		GetGregorianEraYearDay(TclDateFields *, int);
 static void		GetMonthDay(TclDateFields *);
-static void		GetJulianDayFromEraYearWeekDay(TclDateFields *, int);
-static void		GetJulianDayFromEraYearMonthDay(TclDateFields *, int);
-static int		IsGregorianLeapYear(TclDateFields *);
 static Tcl_WideInt	WeekdayOnOrBefore(int, Tcl_WideInt);
 static Tcl_ObjCmdProc ClockClicksObjCmd;
 static Tcl_ObjCmdProc ClockConvertlocaltoutcObjCmd;
+
+static int		ClockGetDateFields(void *clientData,
+			    Tcl_Interp *interp, TclDateFields *fields,
+			    Tcl_Obj *timezoneObj, int changeover);
 static Tcl_ObjCmdProc ClockGetdatefieldsObjCmd;
 static Tcl_ObjCmdProc ClockGetjuliandayfromerayearmonthdayObjCmd;
 static Tcl_ObjCmdProc ClockGetjuliandayfromerayearweekdayObjCmd;
 static Tcl_ObjCmdProc ClockGetenvObjCmd;
 static Tcl_ObjCmdProc ClockMicrosecondsObjCmd;
 static Tcl_ObjCmdProc ClockMillisecondsObjCmd;
-static Tcl_ObjCmdProc ClockParseformatargsObjCmd;
 static Tcl_ObjCmdProc ClockSecondsObjCmd;
+static Tcl_ObjCmdProc ClockFormatObjCmd;
+static Tcl_ObjCmdProc ClockScanObjCmd;
+static int		ClockScanCommit(
+			    DateInfo *info,
+			    ClockFmtScnCmdArgs *opts);
+static int		ClockFreeScan(
+			    DateInfo *info,
+			    Tcl_Obj *strObj, ClockFmtScnCmdArgs *opts);
+static int		ClockCalcRelTime(
+			    DateInfo *info);
+static Tcl_ObjCmdProc ClockAddObjCmd;
+static int		ClockValidDate(
+			    DateInfo *,
+			    ClockFmtScnCmdArgs *, int stage);
 static struct tm *	ThreadSafeLocalTime(const time_t *);
-static void		TzsetIfNecessary(void);
+static size_t		TzsetIfNecessary(void);
 static void		ClockDeleteCmdProc(void *);
 
+static Tcl_ObjCmdProc ClockSafeCatchCmd;
 /*
  * Structure containing description of "native" clock commands to create.
  */
@@ -179,22 +129,31 @@ struct ClockCommand {
     const char *name;		/* The tail of the command name. The full name
 				 * is "::tcl::clock::<name>". When NULL marks
 				 * the end of the table. */
-    Tcl_ObjCmdProc *objCmdProc;	/* Function that implements the command. This
+    Tcl_ObjCmdProc *objCmdProc; /* Function that implements the command. This
 				 * will always have the ClockClientData sent
 				 * to it, but may well ignore this data. */
+    CompileProc *compileProc;	/* The compiler for the command. */
+    void *clientData;	/* Any clientData to give the command (if NULL
+    				 * a reference to ClockClientData will be sent) */
 };
 
 static const struct ClockCommand clockCommands[] = {
-    {"getenv",			ClockGetenvObjCmd},
-    {"Oldscan",		TclClockOldscanObjCmd},
-    {"ConvertLocalToUTC",	ClockConvertlocaltoutcObjCmd},
-    {"GetDateFields",		ClockGetdatefieldsObjCmd},
+    {"add",		ClockAddObjCmd,		TclCompileBasicMin1ArgCmd, NULL},
+    {"clicks",		ClockClicksObjCmd,	TclCompileClockClicksCmd,  NULL},
+    {"format",		ClockFormatObjCmd,	TclCompileBasicMin1ArgCmd, NULL},
+    {"getenv",		ClockGetenvObjCmd,	TclCompileBasicMin1ArgCmd, NULL},
+    {"microseconds",	ClockMicrosecondsObjCmd,TclCompileClockReadingCmd, INT2PTR(1)},
+    {"milliseconds",	ClockMillisecondsObjCmd,TclCompileClockReadingCmd, INT2PTR(2)},
+    {"scan",		ClockScanObjCmd,	TclCompileBasicMin1ArgCmd, NULL},
+    {"seconds",		ClockSecondsObjCmd,	TclCompileClockReadingCmd, INT2PTR(3)},
+    {"ConvertLocalToUTC", ClockConvertlocaltoutcObjCmd,		NULL, NULL},
+    {"GetDateFields",	  ClockGetdatefieldsObjCmd,		NULL, NULL},
     {"GetJulianDayFromEraYearMonthDay",
-		ClockGetjuliandayfromerayearmonthdayObjCmd},
+		ClockGetjuliandayfromerayearmonthdayObjCmd,	NULL, NULL},
     {"GetJulianDayFromEraYearWeekDay",
-		ClockGetjuliandayfromerayearweekdayObjCmd},
-    {"ParseFormatArgs",	ClockParseformatargsObjCmd},
-    {NULL, NULL}
+		ClockGetjuliandayfromerayearweekdayObjCmd,	NULL, NULL},
+    {"catch",		ClockSafeCatchCmd,	TclCompileBasicMin1ArgCmd, NULL},
+    {NULL, NULL, NULL, NULL}
 };
 
 /*
@@ -223,22 +182,10 @@ TclClockInit(
     char cmdName[50];		/* Buffer large enough to hold the string
 				 *::tcl::clock::GetJulianDayFromEraYearMonthDay
 				 * plus a terminating NUL. */
+    Command         *cmdPtr;
     ClockClientData *data;
     int i;
 
-    /* Structure of the 'clock' ensemble */
-
-    static const EnsembleImplMap clockImplMap[] = {
-	{"add",          NULL,                    TclCompileBasicMin1ArgCmd, NULL, NULL,       0},
-	{"clicks",       ClockClicksObjCmd,       TclCompileClockClicksCmd,  NULL, NULL,       0},
-	{"format",       NULL,                    TclCompileBasicMin1ArgCmd, NULL, NULL,       0},
-	{"microseconds", ClockMicrosecondsObjCmd, TclCompileClockReadingCmd, NULL, INT2PTR(1), 0},
-	{"milliseconds", ClockMillisecondsObjCmd, TclCompileClockReadingCmd, NULL, INT2PTR(2), 0},
-	{"scan",         NULL,                    TclCompileBasicMin1ArgCmd, NULL, NULL      , 0},
-	{"seconds",      ClockSecondsObjCmd,      TclCompileClockReadingCmd, NULL, INT2PTR(3), 0},
-	{NULL,           NULL,                    NULL,                      NULL, NULL,       0}
-    };
-
     /*
      * Safe interps get [::clock] as alias to a parent, so do not need their
      * own copies of the support routines.
@@ -256,27 +203,1197 @@ TclClockInit(
     data->refCount = 0;
     data->literals = (Tcl_Obj **)Tcl_Alloc(LIT__END * sizeof(Tcl_Obj*));
     for (i = 0; i < LIT__END; ++i) {
-	data->literals[i] = Tcl_NewStringObj(literals[i], -1);
-	Tcl_IncrRefCount(data->literals[i]);
+	Tcl_InitObjRef(data->literals[i], Tcl_NewStringObj(Literals[i], -1));
     }
+    data->mcLiterals = NULL;
+    data->mcLitIdxs = NULL;
+    data->mcDicts = NULL;
+    data->lastTZEpoch = 0;
+    data->currentYearCentury = ClockDefaultYearCentury;
+    data->yearOfCenturySwitch = ClockDefaultCenturySwitch;
+    data->validMinYear = INT_MIN;
+    data->validMaxYear = INT_MAX;
+    /* corresponds max of JDN in sqlite - 9999-12-31 23:59:59 per default */
+    data->maxJDN = 5373484.499999994;
+
+    data->systemTimeZone = NULL;
+    data->systemSetupTZData = NULL;
+    data->gmtSetupTimeZoneUnnorm = NULL;
+    data->gmtSetupTimeZone = NULL;
+    data->gmtSetupTZData = NULL;
+    data->gmtTZName = NULL;
+    data->lastSetupTimeZoneUnnorm = NULL;
+    data->lastSetupTimeZone = NULL;
+    data->lastSetupTZData = NULL;
+    data->prevSetupTimeZoneUnnorm = NULL;
+    data->prevSetupTimeZone = NULL;
+    data->prevSetupTZData = NULL;
+
+    data->defaultLocale = NULL;
+    data->defaultLocaleDict = NULL;
+    data->currentLocale = NULL;
+    data->currentLocaleDict = NULL;
+    data->lastUsedLocaleUnnorm = NULL;
+    data->lastUsedLocale = NULL;
+    data->lastUsedLocaleDict = NULL;
+    data->prevUsedLocaleUnnorm = NULL;
+    data->prevUsedLocale = NULL;
+    data->prevUsedLocaleDict = NULL;
+
+    data->lastBase.timezoneObj = NULL;
+
+    memset(&data->lastTZOffsCache, 0, sizeof(data->lastTZOffsCache));
+
+    data->defFlags = 0;
 
     /*
      * Install the commands.
-     * TODO - Let Tcl_MakeEnsemble do this?
      */
 
 #define TCL_CLOCK_PREFIX_LEN 14 /* == strlen("::tcl::clock::") */
     memcpy(cmdName, "::tcl::clock::", TCL_CLOCK_PREFIX_LEN);
     for (clockCmdPtr=clockCommands ; clockCmdPtr->name!=NULL ; clockCmdPtr++) {
+    	void *clientData;
+
 	strcpy(cmdName + TCL_CLOCK_PREFIX_LEN, clockCmdPtr->name);
-	data->refCount++;
-	Tcl_CreateObjCommand(interp, cmdName, clockCmdPtr->objCmdProc, data,
-		ClockDeleteCmdProc);
+	if (!(clientData = clockCmdPtr->clientData)) {
+	    clientData = data;
+	    data->refCount++;
+	}
+	cmdPtr = (Command *)Tcl_CreateObjCommand(interp, cmdName,
+		clockCmdPtr->objCmdProc, clientData,
+		clockCmdPtr->clientData ? NULL : ClockDeleteCmdProc);
+	cmdPtr->compileProc = clockCmdPtr->compileProc ?
+		clockCmdPtr->compileProc : TclCompileBasicMin0ArgCmd;
+    }
+    cmdPtr = (Command *)Tcl_CreateObjCommand(interp,
+	    "::tcl::unsupported::clock::configure",
+	    ClockConfigureObjCmd, data, NULL);
+    data->refCount++;
+    cmdPtr->compileProc = TclCompileBasicMin0ArgCmd;
+}
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * ClockConfigureClear --
+ *
+ *	Clean up cached resp. run-time storages used in clock commands.
+ *
+ *	Shared usage for clean-up (ClockDeleteCmdProc) and "configure -clear".
+ *
+ * Results:
+ *	None.
+ *
+ *----------------------------------------------------------------------
+ */
+
+static void
+ClockConfigureClear(
+    ClockClientData *data)
+{
+    ClockFrmScnClearCaches();
+
+    data->lastTZEpoch = 0;
+    Tcl_UnsetObjRef(data->systemTimeZone);
+    Tcl_UnsetObjRef(data->systemSetupTZData);
+    Tcl_UnsetObjRef(data->gmtSetupTimeZoneUnnorm);
+    Tcl_UnsetObjRef(data->gmtSetupTimeZone);
+    Tcl_UnsetObjRef(data->gmtSetupTZData);
+    Tcl_UnsetObjRef(data->gmtTZName);
+    Tcl_UnsetObjRef(data->lastSetupTimeZoneUnnorm);
+    Tcl_UnsetObjRef(data->lastSetupTimeZone);
+    Tcl_UnsetObjRef(data->lastSetupTZData);
+    Tcl_UnsetObjRef(data->prevSetupTimeZoneUnnorm);
+    Tcl_UnsetObjRef(data->prevSetupTimeZone);
+    Tcl_UnsetObjRef(data->prevSetupTZData);
+
+    Tcl_UnsetObjRef(data->defaultLocale);
+    data->defaultLocaleDict = NULL;
+    Tcl_UnsetObjRef(data->currentLocale);
+    data->currentLocaleDict = NULL;
+    Tcl_UnsetObjRef(data->lastUsedLocaleUnnorm);
+    Tcl_UnsetObjRef(data->lastUsedLocale);
+    data->lastUsedLocaleDict = NULL;
+    Tcl_UnsetObjRef(data->prevUsedLocaleUnnorm);
+    Tcl_UnsetObjRef(data->prevUsedLocale);
+    data->prevUsedLocaleDict = NULL;
+
+    Tcl_UnsetObjRef(data->lastBase.timezoneObj);
+
+    Tcl_UnsetObjRef(data->lastTZOffsCache[0].timezoneObj);
+    Tcl_UnsetObjRef(data->lastTZOffsCache[0].tzName);
+    Tcl_UnsetObjRef(data->lastTZOffsCache[1].timezoneObj);
+    Tcl_UnsetObjRef(data->lastTZOffsCache[1].tzName);
+
+    Tcl_UnsetObjRef(data->mcDicts);
+}
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * ClockDeleteCmdProc --
+ *
+ *	Remove a reference to the clock client data, and clean up memory
+ *	when it's all gone.
+ *
+ * Results:
+ *	None.
+ *
+ *----------------------------------------------------------------------
+ */
+static void
+ClockDeleteCmdProc(
+    void *clientData)	/* Opaque pointer to the client data */
+{
+    ClockClientData *data = (ClockClientData *)clientData;
+    int i;
+
+    if (data->refCount-- <= 1) {
+	for (i = 0; i < LIT__END; ++i) {
+	    Tcl_DecrRefCount(data->literals[i]);
+	}
+	if (data->mcLiterals != NULL) {
+	    for (i = 0; i < MCLIT__END; ++i) {
+		Tcl_DecrRefCount(data->mcLiterals[i]);
+	    }
+	    data->mcLiterals = NULL;
+	}
+	if (data->mcLitIdxs != NULL) {
+	    for (i = 0; i < MCLIT__END; ++i) {
+		Tcl_DecrRefCount(data->mcLitIdxs[i]);
+	    }
+	    data->mcLitIdxs = NULL;
+	}
+
+	ClockConfigureClear(data);
+
+	Tcl_Free(data->literals);
+	Tcl_Free(data);
+    }
+}
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * SavePrevTimezoneObj --
+ *
+ *	Used to store previously used/cached time zone (makes it reusable).
+ *
+ *	This enables faster switch between time zones (e. g. to convert from one to another).
+ *
+ * Results:
+ *	None.
+ *
+ *----------------------------------------------------------------------
+ */
+
+static inline void
+SavePrevTimezoneObj(
+    ClockClientData *dataPtr)	/* Client data containing literal pool */
+{
+    Tcl_Obj *timezoneObj = dataPtr->lastSetupTimeZone;
+    if (timezoneObj && timezoneObj != dataPtr->prevSetupTimeZone) {
+	Tcl_SetObjRef(dataPtr->prevSetupTimeZoneUnnorm, dataPtr->lastSetupTimeZoneUnnorm);
+	Tcl_SetObjRef(dataPtr->prevSetupTimeZone, timezoneObj);
+	Tcl_SetObjRef(dataPtr->prevSetupTZData, dataPtr->lastSetupTZData);
+    }
+}
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * NormTimezoneObj --
+ *
+ *	Normalizes the timezone object (used for caching puposes).
+ *
+ *	If already cached time zone could be found, returns this
+ *	object (last setup or last used, system (current) or gmt).
+ *
+ * Results:
+ *	Normalized tcl object pointer.
+ *
+ *----------------------------------------------------------------------
+ */
+
+static Tcl_Obj *
+NormTimezoneObj(
+    ClockClientData *dataPtr,	/* Client data containing literal pool */
+    Tcl_Obj	*timezoneObj,	/* Name of zone to find */
+    int		*loaded)	/* Used to recognized TZ was loaded */
+{
+    const char *tz;
+
+    *loaded = 1;
+    if ( timezoneObj == dataPtr->lastSetupTimeZoneUnnorm
+      && dataPtr->lastSetupTimeZone != NULL
+    ) {
+	return dataPtr->lastSetupTimeZone;
+    }
+    if ( timezoneObj == dataPtr->prevSetupTimeZoneUnnorm
+      && dataPtr->prevSetupTimeZone != NULL
+    ) {
+    	return dataPtr->prevSetupTimeZone;
+    }
+    if (timezoneObj == dataPtr->gmtSetupTimeZoneUnnorm
+      && dataPtr->gmtSetupTimeZone != NULL
+    ) {
+	return dataPtr->literals[LIT_GMT];
+    }
+    if ( timezoneObj == dataPtr->lastSetupTimeZone
+      || timezoneObj == dataPtr->prevSetupTimeZone
+      || timezoneObj == dataPtr->gmtSetupTimeZone
+      || timezoneObj == dataPtr->systemTimeZone
+    ) {
+	return timezoneObj;
+    }
+
+    tz = TclGetString(timezoneObj);
+    if (dataPtr->lastSetupTimeZone != NULL &&
+	strcmp(tz, TclGetString(dataPtr->lastSetupTimeZone)) == 0
+    ) {
+	Tcl_SetObjRef(dataPtr->lastSetupTimeZoneUnnorm, timezoneObj);
+	return dataPtr->lastSetupTimeZone;
+    }
+    if (dataPtr->prevSetupTimeZone != NULL &&
+	strcmp(tz, TclGetString(dataPtr->prevSetupTimeZone)) == 0
+    ) {
+	Tcl_SetObjRef(dataPtr->prevSetupTimeZoneUnnorm, timezoneObj);
+	return dataPtr->prevSetupTimeZone;
+    }
+    if (dataPtr->systemTimeZone != NULL &&
+	strcmp(tz, TclGetString(dataPtr->systemTimeZone)) == 0
+    ) {
+	return dataPtr->systemTimeZone;
+    }
+    if (strcmp(tz, Literals[LIT_GMT]) == 0) {
+	Tcl_SetObjRef(dataPtr->gmtSetupTimeZoneUnnorm, timezoneObj);
+	if (dataPtr->gmtSetupTimeZone == NULL) {
+	    *loaded = 0;
+	}
+	return dataPtr->literals[LIT_GMT];
+    }
+    /* unknown/unloaded tz - recache/revalidate later as last-setup if needed */
+    *loaded = 0;
+    return timezoneObj;
+}
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * ClockGetSystemLocale --
+ *
+ *	Returns system locale.
+ *
+ *	Executes ::tcl::clock::GetSystemLocale in given interpreter.
+ *
+ * Results:
+ *	Returns system locale tcl object.
+ *
+ *----------------------------------------------------------------------
+ */
+
+static inline Tcl_Obj *
+ClockGetSystemLocale(
+    ClockClientData *dataPtr,	/* Opaque pointer to literal pool, etc. */
+    Tcl_Interp *interp)		/* Tcl interpreter */
+{
+    if (Tcl_EvalObjv(interp, 1, &dataPtr->literals[LIT_GETSYSTEMLOCALE], 0) != TCL_OK) {
+	return NULL;
+    }
+
+    return Tcl_GetObjResult(interp);
+}
+/*
+ *----------------------------------------------------------------------
+ *
+ * ClockGetCurrentLocale --
+ *
+ *	Returns current locale.
+ *
+ *	Executes ::tcl::clock::mclocale in given interpreter.
+ *
+ * Results:
+ *	Returns current locale tcl object.
+ *
+ *----------------------------------------------------------------------
+ */
+
+static inline Tcl_Obj *
+ClockGetCurrentLocale(
+    ClockClientData *dataPtr,	/* Client data containing literal pool */
+    Tcl_Interp *interp)		/* Tcl interpreter */
+{
+    if (Tcl_EvalObjv(interp, 1, &dataPtr->literals[LIT_GETCURRENTLOCALE], 0) != TCL_OK) {
+	return NULL;
+    }
+
+    Tcl_SetObjRef(dataPtr->currentLocale, Tcl_GetObjResult(interp));
+    dataPtr->currentLocaleDict = NULL;
+    Tcl_ResetResult(interp);
+
+    return dataPtr->currentLocale;
+}
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * SavePrevLocaleObj --
+ *
+ *	Used to store previously used/cached locale (makes it reusable).
+ *
+ *	This enables faster switch between locales (e. g. to convert from one to another).
+ *
+ * Results:
+ *	None.
+ *
+ *----------------------------------------------------------------------
+ */
+
+static inline void
+SavePrevLocaleObj(
+    ClockClientData *dataPtr)	/* Client data containing literal pool */
+{
+    Tcl_Obj *localeObj = dataPtr->lastUsedLocale;
+    if (localeObj && localeObj != dataPtr->prevUsedLocale) {
+	Tcl_SetObjRef(dataPtr->prevUsedLocaleUnnorm, dataPtr->lastUsedLocaleUnnorm);
+	Tcl_SetObjRef(dataPtr->prevUsedLocale, localeObj);
+	/* mcDicts owns reference to dict */
+	dataPtr->prevUsedLocaleDict = dataPtr->lastUsedLocaleDict;
+    }
+}
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * NormLocaleObj --
+ *
+ *	Normalizes the locale object (used for caching puposes).
+ *
+ *	If already cached locale could be found, returns this
+ *	object (current, system (OS) or last used locales).
+ *
+ * Results:
+ *	Normalized tcl object pointer.
+ *
+ *----------------------------------------------------------------------
+ */
+
+static Tcl_Obj *
+NormLocaleObj(
+    ClockClientData *dataPtr,	/* Client data containing literal pool */
+    Tcl_Interp *interp,		/* Tcl interpreter */
+    Tcl_Obj    *localeObj,
+    Tcl_Obj   **mcDictObj)
+{
+    const char *loc, *loc2;
+    if ( localeObj == NULL
+      || localeObj == dataPtr->literals[LIT_C]
+      || localeObj == dataPtr->defaultLocale
+    ) {
+	*mcDictObj = dataPtr->defaultLocaleDict;
+	return dataPtr->defaultLocale ?
+		    dataPtr->defaultLocale : dataPtr->literals[LIT_C];
+    }
+    if ( localeObj == dataPtr->currentLocale
+      || localeObj == dataPtr->literals[LIT_CURRENT]
+    ) {
+	if (dataPtr->currentLocale == NULL) {
+	    ClockGetCurrentLocale(dataPtr, interp);
+	}
+	*mcDictObj = dataPtr->currentLocaleDict;
+	return dataPtr->currentLocale;
+    }
+    if ( localeObj == dataPtr->lastUsedLocale
+      || localeObj == dataPtr->lastUsedLocaleUnnorm
+    ) {
+	*mcDictObj = dataPtr->lastUsedLocaleDict;
+	return dataPtr->lastUsedLocale;
+    }
+    if ( localeObj == dataPtr->prevUsedLocale
+      || localeObj == dataPtr->prevUsedLocaleUnnorm
+    ) {
+	*mcDictObj = dataPtr->prevUsedLocaleDict;
+	return dataPtr->prevUsedLocale;
+    }
+
+    loc = TclGetString(localeObj);
+    if ( dataPtr->currentLocale != NULL
+      && ( localeObj == dataPtr->currentLocale
+       || (localeObj->length == dataPtr->currentLocale->length
+	  && strcasecmp(loc, TclGetString(dataPtr->currentLocale)) == 0
+	)
+      )
+    ) {
+	*mcDictObj = dataPtr->currentLocaleDict;
+	return dataPtr->currentLocale;
+    }
+    if ( dataPtr->lastUsedLocale != NULL
+      && ( localeObj == dataPtr->lastUsedLocale
+       || (localeObj->length == dataPtr->lastUsedLocale->length
+	  && strcasecmp(loc, TclGetString(dataPtr->lastUsedLocale)) == 0
+	)
+      )
+    ) {
+	*mcDictObj = dataPtr->lastUsedLocaleDict;
+	Tcl_SetObjRef(dataPtr->lastUsedLocaleUnnorm, localeObj);
+	return dataPtr->lastUsedLocale;
+    }
+    if ( dataPtr->prevUsedLocale != NULL
+      && ( localeObj == dataPtr->prevUsedLocale
+       || (localeObj->length == dataPtr->prevUsedLocale->length
+	  && strcasecmp(loc, TclGetString(dataPtr->prevUsedLocale)) == 0
+	)
+      )
+    ) {
+	*mcDictObj = dataPtr->prevUsedLocaleDict;
+	Tcl_SetObjRef(dataPtr->prevUsedLocaleUnnorm, localeObj);
+	return dataPtr->prevUsedLocale;
+    }
+    if (
+	 (localeObj->length == 1 /* C */
+	   && strcasecmp(loc, Literals[LIT_C]) == 0)
+      || (dataPtr->defaultLocale && (loc2 = TclGetString(dataPtr->defaultLocale))
+      	   && localeObj->length == dataPtr->defaultLocale->length
+	   && strcasecmp(loc, loc2) == 0)
+    ) {
+	*mcDictObj = dataPtr->defaultLocaleDict;
+	return dataPtr->defaultLocale ?
+		    dataPtr->defaultLocale : dataPtr->literals[LIT_C];
+    }
+    if ( localeObj->length == 7 /* current */
+      && strcasecmp(loc, Literals[LIT_CURRENT]) == 0
+    ) {
+	if (dataPtr->currentLocale == NULL) {
+	    ClockGetCurrentLocale(dataPtr, interp);
+	}
+	*mcDictObj = dataPtr->currentLocaleDict;
+	return dataPtr->currentLocale;
+    }
+    if (
+	 (localeObj->length == 6 /* system */
+	   && strcasecmp(loc, Literals[LIT_SYSTEM]) == 0)
+    ) {
+	SavePrevLocaleObj(dataPtr);
+	Tcl_SetObjRef(dataPtr->lastUsedLocaleUnnorm, localeObj);
+	localeObj = ClockGetSystemLocale(dataPtr, interp);
+	Tcl_SetObjRef(dataPtr->lastUsedLocale, localeObj);
+	*mcDictObj = NULL;
+	return localeObj;
+    }
+    *mcDictObj = NULL;
+    return localeObj;
+}
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * ClockMCDict --
+ *
+ *	Retrieves a localized storage dictionary object for the given
+ *	locale object.
+ *
+ *	This corresponds with call `::tcl::clock::mcget locale`.
+ *	Cached representation stored in options (for further access).
+ *
+ * Results:
+ *	Tcl-object contains smart reference to msgcat dictionary.
+ *
+ *----------------------------------------------------------------------
+ */
+
+Tcl_Obj *
+ClockMCDict(ClockFmtScnCmdArgs *opts)
+{
+    ClockClientData *dataPtr = (ClockClientData *)opts->clientData;
+
+    /* if dict not yet retrieved */
+    if (opts->mcDictObj == NULL) {
+
+	/* if locale was not yet used */
+	if ( !(opts->flags & CLF_LOCALE_USED) ) {
+
+	    opts->localeObj = NormLocaleObj((ClockClientData *)opts->clientData, opts->interp,
+		opts->localeObj, &opts->mcDictObj);
+
+	    if (opts->localeObj == NULL) {
+		Tcl_SetObjResult(opts->interp,
+		    Tcl_NewStringObj("locale not specified and no default locale set", -1));
+		Tcl_SetErrorCode(opts->interp, "CLOCK", "badOption", (char *)NULL);
+		return NULL;
+	    }
+	    opts->flags |= CLF_LOCALE_USED;
+
+	    /* check locale literals already available (on demand creation) */
+	    if (dataPtr->mcLiterals == NULL) {
+		int i;
+		dataPtr->mcLiterals = (Tcl_Obj **)Tcl_Alloc(MCLIT__END * sizeof(Tcl_Obj*));
+		for (i = 0; i < MCLIT__END; ++i) {
+		    Tcl_InitObjRef(dataPtr->mcLiterals[i],
+			Tcl_NewStringObj(MsgCtLiterals[i], -1));
+		}
+	    }
+	}
+
+	/* check or obtain mcDictObj (be sure it's modifiable) */
+	if (opts->mcDictObj == NULL || opts->mcDictObj->refCount > 1) {
+	    int ref = 1;
+
+	    /* first try to find locale catalog dict */
+	    if (dataPtr->mcDicts == NULL) {
+		Tcl_SetObjRef(dataPtr->mcDicts, Tcl_NewDictObj());
+	    }
+	    Tcl_DictObjGet(NULL, dataPtr->mcDicts,
+		opts->localeObj, &opts->mcDictObj);
+
+	    if (opts->mcDictObj == NULL) {
+		/* get msgcat dictionary - ::tcl::clock::mcget locale */
+		Tcl_Obj *callargs[2];
+
+		callargs[0] = dataPtr->literals[LIT_MCGET];
+		callargs[1] = opts->localeObj;
+
+		if (Tcl_EvalObjv(opts->interp, 2, callargs, 0) != TCL_OK) {
+		    return NULL;
+		}
+
+		opts->mcDictObj = Tcl_GetObjResult(opts->interp);
+		Tcl_ResetResult(opts->interp);
+		ref = 0; /* new object is not yet referenced */
+	    }
+
+	    /* be sure that object reference doesn't increase (dict changeable) */
+	    if (opts->mcDictObj->refCount > ref) {
+		/* smart reference (shared dict as object with no ref-counter) */
+		opts->mcDictObj = TclDictObjSmartRef(opts->interp,
+		    opts->mcDictObj);
+	    }
+
+	    /* create exactly one reference to catalog / make it searchable for future */
+	    Tcl_DictObjPut(NULL, dataPtr->mcDicts, opts->localeObj,
+		opts->mcDictObj);
+
+	    if ( opts->localeObj == dataPtr->literals[LIT_C]
+	      || opts->localeObj == dataPtr->defaultLocale
+	    ) {
+		dataPtr->defaultLocaleDict = opts->mcDictObj;
+	    }
+	    if ( opts->localeObj == dataPtr->currentLocale ) {
+		dataPtr->currentLocaleDict = opts->mcDictObj;
+	    } else if ( opts->localeObj == dataPtr->lastUsedLocale ) {
+		dataPtr->lastUsedLocaleDict = opts->mcDictObj;
+	    } else {
+		SavePrevLocaleObj(dataPtr);
+		Tcl_SetObjRef(dataPtr->lastUsedLocale, opts->localeObj);
+		Tcl_UnsetObjRef(dataPtr->lastUsedLocaleUnnorm);
+		dataPtr->lastUsedLocaleDict = opts->mcDictObj;
+	    }
+	}
+    }
+
+    return opts->mcDictObj;
+}
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * ClockMCGet --
+ *
+ *	Retrieves a msgcat value for the given literal integer mcKey
+ *	from localized storage (corresponding given locale object)
+ *	by mcLiterals[mcKey] (e. g. MONTHS_FULL).
+ *
+ * Results:
+ *	Tcl-object contains localized value.
+ *
+ *----------------------------------------------------------------------
+ */
+
+Tcl_Obj *
+ClockMCGet(
+    ClockFmtScnCmdArgs *opts,
+    int mcKey)
+{
+    ClockClientData *dataPtr = (ClockClientData *)opts->clientData;
+
+    Tcl_Obj *valObj = NULL;
+
+    if (opts->mcDictObj == NULL) {
+	ClockMCDict(opts);
+	if (opts->mcDictObj == NULL)
+	    return NULL;
+    }
+
+    Tcl_DictObjGet(opts->interp, opts->mcDictObj,
+	dataPtr->mcLiterals[mcKey], &valObj);
+
+    return valObj; /* or NULL in obscure case if Tcl_DictObjGet failed */
+}
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * ClockMCGetIdx --
+ *
+ *	Retrieves an indexed msgcat value for the given literal integer mcKey
+ *	from localized storage (corresponding given locale object)
+ *	by mcLitIdxs[mcKey] (e. g. _IDX_MONTHS_FULL).
+ *
+ * Results:
+ *	Tcl-object contains localized indexed value.
+ *
+ *----------------------------------------------------------------------
+ */
+
+MODULE_SCOPE Tcl_Obj *
+ClockMCGetIdx(
+    ClockFmtScnCmdArgs *opts,
+    int mcKey)
+{
+    ClockClientData *dataPtr = (ClockClientData *)opts->clientData;
+
+    Tcl_Obj *valObj = NULL;
+
+    if (opts->mcDictObj == NULL) {
+	ClockMCDict(opts);
+	if (opts->mcDictObj == NULL)
+	    return NULL;
+    }
+
+    /* try to get indices object */
+    if (dataPtr->mcLitIdxs == NULL) {
+	return NULL;
     }
 
-    /* Make the clock ensemble */
+    if (Tcl_DictObjGet(NULL, opts->mcDictObj,
+	dataPtr->mcLitIdxs[mcKey], &valObj) != TCL_OK
+    ) {
+	return NULL;
+    }
 
-    TclMakeEnsemble(interp, "clock", clockImplMap);
+    return valObj;
+}
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * ClockMCSetIdx --
+ *
+ *	Sets an indexed msgcat value for the given literal integer mcKey
+ *	in localized storage (corresponding given locale object)
+ *	by mcLitIdxs[mcKey] (e. g. _IDX_MONTHS_FULL).
+ *
+ * Results:
+ *	Returns a standard Tcl result.
+ *
+ *----------------------------------------------------------------------
+ */
+
+int
+ClockMCSetIdx(
+    ClockFmtScnCmdArgs *opts,
+    int mcKey, Tcl_Obj *valObj)
+{
+    ClockClientData *dataPtr = (ClockClientData *)opts->clientData;
+
+    if (opts->mcDictObj == NULL) {
+	ClockMCDict(opts);
+	if (opts->mcDictObj == NULL)
+	    return TCL_ERROR;
+    }
+
+    /* if literal storage for indices not yet created */
+    if (dataPtr->mcLitIdxs == NULL) {
+	int i;
+	dataPtr->mcLitIdxs = (Tcl_Obj **)Tcl_Alloc(MCLIT__END * sizeof(Tcl_Obj*));
+	for (i = 0; i < MCLIT__END; ++i) {
+	    Tcl_InitObjRef(dataPtr->mcLitIdxs[i],
+		Tcl_NewStringObj(MsgCtLitIdxs[i], -1));
+	}
+    }
+
+    return Tcl_DictObjPut(opts->interp, opts->mcDictObj,
+	    dataPtr->mcLitIdxs[mcKey], valObj);
+}
+
+static void
+TimezoneLoaded(
+    ClockClientData *dataPtr,
+    Tcl_Obj	*timezoneObj,	/* Name of zone was loaded */
+    Tcl_Obj	*tzUnnormObj)	/* Name of zone was loaded */
+{
+    /* don't overwrite last-setup with GMT (special case) */
+    if (timezoneObj == dataPtr->literals[LIT_GMT]) {
+	/* mark GMT zone loaded */
+	if (dataPtr->gmtSetupTimeZone == NULL) {
+	    Tcl_SetObjRef(dataPtr->gmtSetupTimeZone,
+		dataPtr->literals[LIT_GMT]);
+	}
+	Tcl_SetObjRef(dataPtr->gmtSetupTimeZoneUnnorm, tzUnnormObj);
+	return;
+    }
+
+    /* last setup zone loaded */
+    if (dataPtr->lastSetupTimeZone != timezoneObj) {
+	SavePrevTimezoneObj(dataPtr);
+	Tcl_SetObjRef(dataPtr->lastSetupTimeZone, timezoneObj);
+	Tcl_UnsetObjRef(dataPtr->lastSetupTZData);
+    }
+    Tcl_SetObjRef(dataPtr->lastSetupTimeZoneUnnorm, tzUnnormObj);
+}
+/*
+ *----------------------------------------------------------------------
+ *
+ * ClockConfigureObjCmd --
+ *
+ *	This function is invoked to process the Tcl "::clock::configure" (internal) command.
+ *
+ * Usage:
+ *	::tcl::unsupported::clock::configure ?-option ?value??
+ *
+ * Results:
+ *	Returns a standard Tcl result.
+ *
+ * Side effects:
+ *	None.
+ *
+ *----------------------------------------------------------------------
+ */
+
+static int
+ClockConfigureObjCmd(
+    void *clientData,  /* Client data containing literal pool */
+    Tcl_Interp *interp,	    /* Tcl interpreter */
+    int objc,		    /* Parameter count */
+    Tcl_Obj *const objv[])  /* Parameter vector */
+{
+    ClockClientData *dataPtr = (ClockClientData *)clientData;
+
+    static const char *const options[] = {
+	"-system-tz",	  "-setup-tz",	  "-default-locale",	"-current-locale",
+	"-clear",
+	"-year-century",  "-century-switch",
+	"-min-year", "-max-year", "-max-jdn", "-validate",
+	"-init-complete",
+	NULL
+    };
+    enum optionInd {
+	CLOCK_SYSTEM_TZ,  CLOCK_SETUP_TZ, CLOCK_DEFAULT_LOCALE, CLOCK_CURRENT_LOCALE,
+	CLOCK_CLEAR_CACHE,
+	CLOCK_YEAR_CENTURY, CLOCK_CENTURY_SWITCH,
+	CLOCK_MIN_YEAR, CLOCK_MAX_YEAR, CLOCK_MAX_JDN, CLOCK_VALIDATE,
+	CLOCK_INIT_COMPLETE
+    };
+    int optionIndex;		/* Index of an option. */
+    int i;
+
+    for (i = 1; i < objc; i++) {
+	if (Tcl_GetIndexFromObj(interp, objv[i++], options,
+	    "option", 0, &optionIndex) != TCL_OK) {
+	    Tcl_SetErrorCode(interp, "CLOCK", "badOption",
+		    Tcl_GetString(objv[i-1]), (char *)NULL);
+	    return TCL_ERROR;
+	}
+	switch (optionIndex) {
+	case CLOCK_SYSTEM_TZ:
+	if (1) {
+	    /* validate current tz-epoch */
+	    size_t lastTZEpoch = TzsetIfNecessary();
+	    if (i < objc) {
+		if (dataPtr->systemTimeZone != objv[i]) {
+		    Tcl_SetObjRef(dataPtr->systemTimeZone, objv[i]);
+		    Tcl_UnsetObjRef(dataPtr->systemSetupTZData);
+		}
+		dataPtr->lastTZEpoch = lastTZEpoch;
+	    }
+	    if (i+1 >= objc && dataPtr->systemTimeZone != NULL
+			 && dataPtr->lastTZEpoch == lastTZEpoch) {
+		Tcl_SetObjResult(interp, dataPtr->systemTimeZone);
+	    }
+	}
+	break;
+	case CLOCK_SETUP_TZ:
+	    if (i < objc) {
+		int loaded;
+		Tcl_Obj *timezoneObj = NormTimezoneObj(dataPtr, objv[i], &loaded);
+		if (!loaded) {
+		    TimezoneLoaded(dataPtr, timezoneObj, objv[i]);
+		}
+		Tcl_SetObjResult(interp, timezoneObj);
+	    }
+	    else
+	    if (i+1 >= objc && dataPtr->lastSetupTimeZone != NULL) {
+		Tcl_SetObjResult(interp, dataPtr->lastSetupTimeZone);
+	    }
+	break;
+	case CLOCK_DEFAULT_LOCALE:
+	    if (i < objc) {
+		if (dataPtr->defaultLocale != objv[i]) {
+		    Tcl_SetObjRef(dataPtr->defaultLocale, objv[i]);
+		    dataPtr->defaultLocaleDict = NULL;
+		}
+	    }
+	    if (i+1 >= objc) {
+		Tcl_SetObjResult(interp, dataPtr->defaultLocale ?
+		    dataPtr->defaultLocale : dataPtr->literals[LIT_C]);
+	    }
+	break;
+	case CLOCK_CURRENT_LOCALE:
+	    if (i < objc) {
+		if (dataPtr->currentLocale != objv[i]) {
+		    Tcl_SetObjRef(dataPtr->currentLocale, objv[i]);
+		    dataPtr->currentLocaleDict = NULL;
+		}
+	    }
+	    if (i+1 >= objc && dataPtr->currentLocale != NULL) {
+		Tcl_SetObjResult(interp, dataPtr->currentLocale);
+	    }
+	break;
+	case CLOCK_YEAR_CENTURY:
+	    if (i < objc) {
+		int year;
+		if (TclGetIntFromObj(interp, objv[i], &year) != TCL_OK) {
+		    return TCL_ERROR;
+		}
+		dataPtr->currentYearCentury = year;
+		if (i+1 >= objc) {
+		    Tcl_SetObjResult(interp, objv[i]);
+		}
+		continue;
+	    }
+	    if (i+1 >= objc) {
+		Tcl_SetObjResult(interp,
+		    Tcl_NewWideIntObj(dataPtr->currentYearCentury));
+	    }
+	break;
+	case CLOCK_CENTURY_SWITCH:
+	    if (i < objc) {
+		int year;
+		if (TclGetIntFromObj(interp, objv[i], &year) != TCL_OK) {
+		    return TCL_ERROR;
+		}
+		dataPtr->yearOfCenturySwitch = year;
+		Tcl_SetObjResult(interp, objv[i]);
+		continue;
+	    }
+	    if (i+1 >= objc) {
+		Tcl_SetObjResult(interp,
+		    Tcl_NewWideIntObj(dataPtr->yearOfCenturySwitch));
+	    }
+	break;
+	case CLOCK_MIN_YEAR:
+	    if (i < objc) {
+		int year;
+		if (TclGetIntFromObj(interp, objv[i], &year) != TCL_OK) {
+		    return TCL_ERROR;
+		}
+		dataPtr->validMinYear = year;
+		Tcl_SetObjResult(interp, objv[i]);
+		continue;
+	    }
+	    if (i+1 >= objc) {
+		Tcl_SetObjResult(interp,
+		    Tcl_NewWideIntObj(dataPtr->validMinYear));
+	    }
+	break;
+	case CLOCK_MAX_YEAR:
+	    if (i < objc) {
+		int year;
+		if (TclGetIntFromObj(interp, objv[i], &year) != TCL_OK) {
+		    return TCL_ERROR;
+		}
+		dataPtr->validMaxYear = year;
+		Tcl_SetObjResult(interp, objv[i]);
+		continue;
+	    }
+	    if (i+1 >= objc) {
+		Tcl_SetObjResult(interp,
+		    Tcl_NewWideIntObj(dataPtr->validMaxYear));
+	    }
+	break;
+	case CLOCK_MAX_JDN:
+	    if (i < objc) {
+		double jd;
+		if (Tcl_GetDoubleFromObj(interp, objv[i], &jd) != TCL_OK) {
+		    return TCL_ERROR;
+		}
+		dataPtr->maxJDN = jd;
+		Tcl_SetObjResult(interp, objv[i]);
+		continue;
+	    }
+	    if (i+1 >= objc) {
+		Tcl_SetObjResult(interp,
+		    Tcl_NewDoubleObj(dataPtr->maxJDN));
+	    }
+	break;
+	case CLOCK_VALIDATE:
+	    if (i < objc) {
+		int val;
+		if (Tcl_GetBooleanFromObj(interp, objv[i], &val) != TCL_OK) {
+		    return TCL_ERROR;
+		}
+		if (val) {
+		    dataPtr->defFlags |= CLF_VALIDATE;
+		} else {
+		    dataPtr->defFlags &= ~CLF_VALIDATE;
+		}
+	    }
+	    if (i+1 >= objc) {
+		Tcl_SetObjResult(interp,
+		    Tcl_NewWideIntObj(dataPtr->defFlags & CLF_VALIDATE ? 1 : 0));
+	    }
+	break;
+	case CLOCK_CLEAR_CACHE:
+	    ClockConfigureClear(dataPtr);
+	break;
+	case CLOCK_INIT_COMPLETE:
+	    {
+		/*
+		 * Init completed.
+		 * Compile clock ensemble (performance purposes).
+		 */
+		Tcl_Command token = Tcl_FindCommand(interp, "::clock",
+		    NULL, TCL_GLOBAL_ONLY);
+		if (!token) {
+		    return TCL_ERROR;
+		}
+		int ensFlags = 0;
+		if (Tcl_GetEnsembleFlags(interp, token, &ensFlags) != TCL_OK) {
+		    return TCL_ERROR;
+		}
+		ensFlags |= ENSEMBLE_COMPILE;
+		if (Tcl_SetEnsembleFlags(interp, token, ensFlags) != TCL_OK) {
+		    return TCL_ERROR;
+		}
+	    }
+	break;
+	}
+    }
+
+    return TCL_OK;
+}
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * ClockGetTZData --
+ *
+ *	Retrieves tzdata table for given normalized timezone.
+ *
+ * Results:
+ *	Returns a tcl object with tzdata.
+ *
+ * Side effects:
+ *	The tzdata can be cached in ClockClientData structure.
+ *
+ *----------------------------------------------------------------------
+ */
+
+static inline Tcl_Obj *
+ClockGetTZData(
+    void *clientData,	/* Opaque pointer to literal pool, etc. */
+    Tcl_Interp *interp,		/* Tcl interpreter */
+    Tcl_Obj *timezoneObj)	/* Name of the timezone */
+{
+    ClockClientData *dataPtr = (ClockClientData *)clientData;
+    Tcl_Obj *ret, **out = NULL;
+
+    /* if cached (if already setup this one) */
+    if ( timezoneObj == dataPtr->lastSetupTimeZone
+      || timezoneObj == dataPtr->lastSetupTimeZoneUnnorm
+    ) {
+	if (dataPtr->lastSetupTZData != NULL) {
+	    return dataPtr->lastSetupTZData;
+	}
+	out = &dataPtr->lastSetupTZData;
+    }
+    /* differentiate GMT and system zones, because used often */
+    /* simple caching, because almost used the tz-data of last timezone
+     */
+    if (timezoneObj == dataPtr->systemTimeZone) {
+	if (dataPtr->systemSetupTZData != NULL) {
+	    return dataPtr->systemSetupTZData;
+	}
+	out = &dataPtr->systemSetupTZData;
+    }
+    else
+    if ( timezoneObj == dataPtr->literals[LIT_GMT]
+      || timezoneObj == dataPtr->gmtSetupTimeZoneUnnorm
+    ) {
+	if (dataPtr->gmtSetupTZData != NULL) {
+	    return dataPtr->gmtSetupTZData;
+	}
+	out = &dataPtr->gmtSetupTZData;
+    }
+    else
+    if ( timezoneObj == dataPtr->prevSetupTimeZone
+      || timezoneObj == dataPtr->prevSetupTimeZoneUnnorm
+    ) {
+	if (dataPtr->prevSetupTZData != NULL) {
+	    return dataPtr->prevSetupTZData;
+	}
+	out = &dataPtr->prevSetupTZData;
+    }
+
+    ret = Tcl_ObjGetVar2(interp, dataPtr->literals[LIT_TZDATA],
+	timezoneObj, TCL_LEAVE_ERR_MSG);
+
+    /* cache using corresponding slot and as last used */
+    if (out != NULL) {
+	Tcl_SetObjRef(*out, ret);
+    }
+    else
+    if (dataPtr->lastSetupTimeZone != timezoneObj) {
+	SavePrevTimezoneObj(dataPtr);
+	Tcl_SetObjRef(dataPtr->lastSetupTimeZone, timezoneObj);
+	Tcl_UnsetObjRef(dataPtr->lastSetupTimeZoneUnnorm);
+	Tcl_SetObjRef(dataPtr->lastSetupTZData, ret);
+    }
+    return ret;
+}
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * ClockGetSystemTimeZone --
+ *
+ *	Returns system (current) timezone.
+ *
+ *	If system zone not yet cached, it executes ::tcl::clock::GetSystemTimeZone
+ *	in given interpreter and caches its result.
+ *
+ * Results:
+ *	Returns normalized timezone object.
+ *
+ *----------------------------------------------------------------------
+ */
+
+static Tcl_Obj *
+ClockGetSystemTimeZone(
+    void *clientData,	/* Opaque pointer to literal pool, etc. */
+    Tcl_Interp *interp)		/* Tcl interpreter */
+{
+    ClockClientData *dataPtr = (ClockClientData *)clientData;
+
+    /* if known (cached and same epoch) - return now */
+    if (dataPtr->systemTimeZone != NULL
+	    && dataPtr->lastTZEpoch == TzsetIfNecessary()) {
+	return dataPtr->systemTimeZone;
+    }
+
+    Tcl_UnsetObjRef(dataPtr->systemTimeZone);
+    Tcl_UnsetObjRef(dataPtr->systemSetupTZData);
+
+    if (Tcl_EvalObjv(interp, 1, &dataPtr->literals[LIT_GETSYSTEMTIMEZONE], 0) != TCL_OK) {
+	return NULL;
+    }
+    if (dataPtr->systemTimeZone == NULL) {
+	Tcl_SetObjRef(dataPtr->systemTimeZone, Tcl_GetObjResult(interp));
+    }
+    Tcl_ResetResult(interp);
+    return dataPtr->systemTimeZone;
+}
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * ClockSetupTimeZone --
+ *
+ *	Sets up the timezone. Loads tzdata, etc.
+ *
+ * Results:
+ *	Returns normalized timezone object.
+ *
+ *----------------------------------------------------------------------
+ */
+
+Tcl_Obj *
+ClockSetupTimeZone(
+    void *clientData,	/* Opaque pointer to literal pool, etc. */
+    Tcl_Interp *interp,		/* Tcl interpreter */
+    Tcl_Obj *timezoneObj)
+{
+    ClockClientData *dataPtr = (ClockClientData *)clientData;
+    int loaded;
+    Tcl_Obj *callargs[2];
+
+    /* if cached (if already setup this one) */
+    if ( timezoneObj == dataPtr->literals[LIT_GMT]
+      && dataPtr->gmtSetupTZData != NULL
+    ) {
+	return timezoneObj;
+    }
+    if ( ( timezoneObj == dataPtr->lastSetupTimeZone
+	|| timezoneObj == dataPtr->lastSetupTimeZoneUnnorm
+      ) && dataPtr->lastSetupTimeZone != NULL
+    ) {
+	return dataPtr->lastSetupTimeZone;
+    }
+    if ( ( timezoneObj == dataPtr->prevSetupTimeZone
+	|| timezoneObj == dataPtr->prevSetupTimeZoneUnnorm
+      ) && dataPtr->prevSetupTimeZone != NULL
+    ) {
+	return dataPtr->prevSetupTimeZone;
+    }
+
+    /* differentiate normalized (last, GMT and system) zones, because used often and already set */
+    callargs[1] = NormTimezoneObj(dataPtr, timezoneObj, &loaded);
+    /* if loaded (setup already called for this TZ) */
+    if (loaded) {
+	return callargs[1];
+    }
+
+    /* before setup just take a look in TZData variable */
+    if (Tcl_ObjGetVar2(interp, dataPtr->literals[LIT_TZDATA], timezoneObj, 0)) {
+    	/* put it to last slot and return normalized */
+    	TimezoneLoaded(dataPtr, callargs[1], timezoneObj);
+	return callargs[1];
+    }
+    /* setup now */
+    callargs[0] = dataPtr->literals[LIT_SETUPTIMEZONE];
+    if (Tcl_EvalObjv(interp, 2, callargs, 0) == TCL_OK) {
+	/* save unnormalized last used */
+	Tcl_SetObjRef(dataPtr->lastSetupTimeZoneUnnorm, timezoneObj);
+	return callargs[1];
+    }
+    return NULL;
+}
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * ClockFormatNumericTimeZone --
+ *
+ *	Formats a time zone as +hhmmss
+ *
+ * Parameters:
+ *	z - Time zone in seconds east of Greenwich
+ *
+ * Results:
+ *	Returns the time zone object (formatted in a numeric form)
+ *
+ * Side effects:
+ *	None.
+ *
+ *----------------------------------------------------------------------
+ */
+
+Tcl_Obj *
+ClockFormatNumericTimeZone(int z) {
+    char buf[12+1], *p;
+
+    if ( z < 0 ) {
+	z = -z;
+	*buf = '-';
+    } else {
+	*buf = '+';
+    }
+    TclItoAw(buf+1, z / 3600, '0', 2);   z %= 3600;
+    p = TclItoAw(buf+3, z / 60, '0', 2); z %= 60;
+    if (z != 0) {
+	p = TclItoAw(buf+5, z, '0', 2);
+    }
+    return Tcl_NewStringObj(buf, p - buf);
 }
 
 /*
@@ -288,11 +1405,11 @@ TclClockInit(
  *	is available.
  *
  * Usage:
- *	::tcl::clock::ConvertUTCToLocal dictionary tzdata changeover
+ *	::tcl::clock::ConvertUTCToLocal dictionary timezone changeover
  *
  * Parameters:
  *	dict - Dictionary containing a 'localSeconds' entry.
- *	tzdata - Time zone data
+ *	timezone - Time zone
  *	changeover - Julian Day of the adoption of the Gregorian calendar.
  *
  * Results:
@@ -321,12 +1438,13 @@ ClockConvertlocaltoutcObjCmd(
     int created = 0;
     int status;
 
+    fields.tzName = NULL;
     /*
      * Check params and convert time.
      */
 
     if (objc != 4) {
-	Tcl_WrongNumArgs(interp, 1, objv, "dict tzdata changeover");
+	Tcl_WrongNumArgs(interp, 1, objv, "dict timezone changeover");
 	return TCL_ERROR;
     }
     dict = objv[1];
@@ -342,7 +1460,7 @@ ClockConvertlocaltoutcObjCmd(
     if ((TclGetWideIntFromObj(interp, secondsObj,
 	    &fields.localSeconds) != TCL_OK)
 	|| (TclGetIntFromObj(interp, objv[3], &changeover) != TCL_OK)
-	|| ConvertLocalToUTC(interp, &fields, objv[2], changeover)) {
+	|| ConvertLocalToUTC(clientData, interp, &fields, objv[2], changeover)) {
 	return TCL_ERROR;
     }
 
@@ -376,12 +1494,11 @@ ClockConvertlocaltoutcObjCmd(
  *	formatting a date, and populates a dictionary with them.
  *
  * Usage:
- *	::tcl::clock::GetDateFields seconds tzdata changeover
+ *	::tcl::clock::GetDateFields seconds timezone changeover
  *
  * Parameters:
  *	seconds - Time expressed in seconds from the Posix epoch.
- *	tzdata - Time zone data of the time zone in which time is to be
- *		 expressed.
+ *	timezone - Time zone in which time is to be expressed.
  *	changeover - Julian Day Number at which the current locale adopted
  *		     the Gregorian calendar
  *
@@ -410,12 +1527,14 @@ ClockGetdatefieldsObjCmd(
     Tcl_Obj *const *lit = data->literals;
     int changeover;
 
+    fields.tzName = NULL;
+
     /*
      * Check params.
      */
 
     if (objc != 4) {
-	Tcl_WrongNumArgs(interp, 1, objv, "seconds tzdata changeover");
+	Tcl_WrongNumArgs(interp, 1, objv, "seconds timezone changeover");
 	return TCL_ERROR;
     }
     if (TclGetWideIntFromObj(interp, objv[1], &fields.seconds) != TCL_OK
@@ -433,30 +1552,14 @@ ClockGetdatefieldsObjCmd(
 	return TCL_ERROR;
     }
 
-    /*
-     * Convert UTC time to local.
-     */
+    /* Extract fields */
 
-    if (ConvertUTCToLocal(interp, &fields, objv[2], changeover) != TCL_OK) {
+    if (ClockGetDateFields(clientData, interp, &fields, objv[2],
+	  changeover) != TCL_OK) {
 	return TCL_ERROR;
     }
 
-    /*
-     * Extract Julian day. Always round the quotient down by subtracting 1
-     * when the remainder is negative (i.e. if the quotient was rounded up).
-     */
-
-    fields.julianDay = (int) ((fields.localSeconds / SECONDS_PER_DAY) -
-	    ((fields.localSeconds % SECONDS_PER_DAY) < 0) +
-	    JULIAN_DAY_POSIX_EPOCH);
-
-    /*
-     * Convert to Julian or Gregorian calendar.
-     */
-
-    GetGregorianEraYearDay(&fields, changeover);
-    GetMonthDay(&fields);
-    GetYearWeekDay(&fields, changeover);
+    /* Make dict of fields */
 
     dict = Tcl_NewDictObj();
     Tcl_DictObjPut(NULL, dict, lit[LIT_LOCALSECONDS],
@@ -495,6 +1598,58 @@ ClockGetdatefieldsObjCmd(
 /*
  *----------------------------------------------------------------------
  *
+ * ClockGetDateFields --
+ *
+ *	Converts given UTC time (seconds in a TclDateFields structure)
+ *	to local time and determines the values that clock routines will
+ *	use in scanning or formatting a date.
+ *
+ * Results:
+ *	Date-time values are stored in structure "fields".
+ *	Returns a standard Tcl result.
+ *
+ *----------------------------------------------------------------------
+ */
+
+int
+ClockGetDateFields(
+    void *clientData,	/* Client data of the interpreter */
+    Tcl_Interp *interp,		/* Tcl interpreter */
+    TclDateFields *fields,	/* Pointer to result fields, where
+				 * fields->seconds contains date to extract */
+    Tcl_Obj *timezoneObj,	/* Time zone object or NULL for gmt */
+    int changeover)		/* Julian Day Number */
+{
+    /*
+     * Convert UTC time to local.
+     */
+
+    if (ConvertUTCToLocal(clientData, interp, fields, timezoneObj,
+	    changeover) != TCL_OK) {
+	return TCL_ERROR;
+    }
+
+    /*
+     * Extract Julian day and seconds of the day.
+     */
+
+    ClockExtractJDAndSODFromSeconds(fields->julianDay, fields->secondOfDay,
+	fields->localSeconds);
+
+    /*
+     * Convert to Julian or Gregorian calendar.
+     */
+
+    GetGregorianEraYearDay(fields, changeover);
+    GetMonthDay(fields);
+    GetYearWeekDay(fields, changeover);
+
+    return TCL_OK;
+}
+
+/*
+ *----------------------------------------------------------------------
+ *
  * ClockGetjuliandayfromerayearmonthdayObjCmd --
  *
  *	Tcl command that converts a time from era-year-month-day to a Julian
@@ -569,6 +1724,8 @@ ClockGetjuliandayfromerayearmonthdayObjCmd(
     int status;
     int isBce = 0;
 
+    fields.tzName = NULL;
+
     /*
      * Check params.
      */
@@ -653,6 +1810,8 @@ ClockGetjuliandayfromerayearweekdayObjCmd(
     int status;
     int isBce = 0;
 
+    fields.tzName = NULL;
+
     /*
      * Check params.
      */
@@ -720,18 +1879,63 @@ ClockGetjuliandayfromerayearweekdayObjCmd(
 
 static int
 ConvertLocalToUTC(
+    void *clientData,	/* Client data of the interpreter */
     Tcl_Interp *interp,		/* Tcl interpreter */
     TclDateFields *fields,	/* Fields of the time */
-    Tcl_Obj *tzdata,		/* Time zone data */
+    Tcl_Obj *timezoneObj,	/* Time zone */
     int changeover)		/* Julian Day of the Gregorian transition */
 {
+    ClockClientData *dataPtr = (ClockClientData *)clientData;
+    Tcl_Obj *tzdata;		/* Time zone data */
     Tcl_Size rowc;			/* Number of rows in tzdata */
     Tcl_Obj **rowv;		/* Pointers to the rows */
+    Tcl_WideInt seconds;
+    ClockLastTZOffs * ltzoc = NULL;
+
+    /* fast phase-out for shared GMT-object (don't need to convert UTC 2 UTC) */
+    if (timezoneObj == dataPtr->literals[LIT_GMT]) {
+	fields->seconds = fields->localSeconds;
+	fields->tzOffset = 0;
+	return TCL_OK;
+    }
+
+    /*
+     * Check cacheable conversion could be used
+     * (last-period UTC2Local cache within the same TZ and seconds)
+     */
+    for (rowc = 0; rowc < 2; rowc++) {
+	ltzoc = &dataPtr->lastTZOffsCache[rowc];
+	if (timezoneObj != ltzoc->timezoneObj || changeover != ltzoc->changeover) {
+	    ltzoc = NULL;
+	    continue;
+	}
+	seconds = fields->localSeconds - ltzoc->tzOffset;
+	if ( seconds >= ltzoc->rangesVal[0]
+	  && seconds <  ltzoc->rangesVal[1]
+	) {
+	    /* the same time zone and offset (UTC time inside the last minute) */
+	    fields->tzOffset = ltzoc->tzOffset;
+	    fields->seconds = seconds;
+	    return TCL_OK;
+	}
+	/* in the DST-hole (because of the check above) - correct localSeconds */
+	if (fields->localSeconds == ltzoc->localSeconds) {
+	    /* the same time zone and offset (but we'll shift local-time) */
+	    fields->tzOffset = ltzoc->tzOffset;
+	    fields->seconds = seconds;
+	    goto dstHole;
+	}
+    }
 
     /*
      * Unpack the tz data.
      */
 
+    tzdata = ClockGetTZData(clientData, interp, timezoneObj);
+    if (tzdata == NULL) {
+	return TCL_ERROR;
+    }
+
     if (TclListObjGetElements(interp, tzdata, &rowc, &rowv) != TCL_OK) {
 	return TCL_ERROR;
     }
@@ -742,10 +1946,59 @@ ConvertLocalToUTC(
      */
 
     if (rowc == 0) {
-	return ConvertLocalToUTCUsingC(interp, fields, changeover);
+
+	if (ConvertLocalToUTCUsingC(interp, fields, changeover) != TCL_OK) {
+	    return TCL_ERROR;
+	};
+
+	/* we cannot cache (ranges unknown yet) - todo: check later the DST-hole here */
+	return TCL_OK;
+
     } else {
-	return ConvertLocalToUTCUsingTable(interp, fields, rowc, rowv);
+	Tcl_WideInt rangesVal[2];
+
+	if (ConvertLocalToUTCUsingTable(interp, fields, rowc, rowv,
+		rangesVal) != TCL_OK) {
+	    return TCL_ERROR;
+	};
+
+	seconds = fields->seconds;
+
+	/* Cache the last conversion */
+	if (ltzoc != NULL) { /* slot was found above */
+	    /* timezoneObj and changeover are the same */
+	    Tcl_SetObjRef(ltzoc->tzName, fields->tzName); /* may be NULL */
+	} else {
+	    /* no TZ in cache - just move second slot down and use the first one */
+	    ltzoc = &dataPtr->lastTZOffsCache[0];
+	    Tcl_UnsetObjRef(dataPtr->lastTZOffsCache[1].timezoneObj);
+	    Tcl_UnsetObjRef(dataPtr->lastTZOffsCache[1].tzName);
+	    memcpy(&dataPtr->lastTZOffsCache[1], ltzoc, sizeof(*ltzoc));
+	    Tcl_InitObjRef(ltzoc->timezoneObj, timezoneObj);
+	    ltzoc->changeover = changeover;
+	    Tcl_InitObjRef(ltzoc->tzName, fields->tzName); /* may be NULL */
+	}
+	ltzoc->localSeconds = fields->localSeconds;
+	ltzoc->rangesVal[0] = rangesVal[0];
+	ltzoc->rangesVal[1] = rangesVal[1];
+	ltzoc->tzOffset = fields->tzOffset;
     }
+
+
+    /* check DST-hole: if retrieved seconds is out of range */
+    if ( ltzoc->rangesVal[0] > seconds || seconds >= ltzoc->rangesVal[1] ) {
+    dstHole:
+	#if 0
+	printf("given local-time is outside the time-zone (in DST-hole): "
+		"%d - offs %d => %d <= %d < %d\n",
+		(int)fields->localSeconds, fields->tzOffset,
+		(int)ltzoc->rangesVal[0], (int)seconds, (int)ltzoc->rangesVal[1]);
+	#endif
+	/* because we don't know real TZ (we're outsize), just invalidate local
+	 * time (which could be verified in ClockValidDate later) */
+	fields->localSeconds = TCL_INV_SECONDS; /* not valid seconds */
+    }
+    return TCL_OK;
 }
 
 /*
@@ -770,16 +2023,19 @@ static int
 ConvertLocalToUTCUsingTable(
     Tcl_Interp *interp,		/* Tcl interpreter */
     TclDateFields *fields,	/* Time to convert, with 'seconds' filled in */
-    Tcl_Size rowc,			/* Number of points at which time changes */
-    Tcl_Obj *const rowv[])	/* Points at which time changes */
+    int rowc,			/* Number of points at which time changes */
+    Tcl_Obj *const rowv[],	/* Points at which time changes */
+    Tcl_WideInt *rangesVal)	/* Return bounds for time period */
 {
     Tcl_Obj *row;
     Tcl_Size cellc;
     Tcl_Obj **cellv;
-    int have[8];
+    struct {
+	Tcl_Obj *tzName;
+	int tzOffset;
+    } have[8];
     int nHave = 0;
-    int i;
-    int found;
+    Tcl_Size i;
 
     /*
      * Perform an initial lookup assuming that local == UTC, and locate the
@@ -791,11 +2047,11 @@ ConvertLocalToUTCUsingTable(
      * Saving Time transition.
      */
 
-    found = 0;
     fields->tzOffset = 0;
     fields->seconds = fields->localSeconds;
-    while (!found) {
-	row = LookupLastTransition(interp, fields->seconds, rowc, rowv);
+    while (1) {
+	row = LookupLastTransition(interp, fields->seconds, rowc, rowv,
+		    rangesVal);
 	if ((row == NULL)
 		|| TclListObjGetElements(interp, row, &cellc,
 		    &cellv) != TCL_OK
@@ -803,23 +2059,24 @@ ConvertLocalToUTCUsingTable(
 		    &fields->tzOffset) != TCL_OK) {
 	    return TCL_ERROR;
 	}
-	found = 0;
-	for (i = 0; !found && i < nHave; ++i) {
-	    if (have[i] == fields->tzOffset) {
-		found = 1;
-		break;
+	for (i = 0; i < nHave; ++i) {
+	    if (have[i].tzOffset == fields->tzOffset) {
+		goto found;
 	    }
 	}
-	if (!found) {
-	    if (nHave == 8) {
-		Tcl_Panic("loop in ConvertLocalToUTCUsingTable");
-	    }
-	    have[nHave++] = fields->tzOffset;
+	if (nHave == 8) {
+	    Tcl_Panic("loop in ConvertLocalToUTCUsingTable");
 	}
+	have[nHave].tzName = cellv[3];
+	have[nHave++].tzOffset = fields->tzOffset;
 	fields->seconds = fields->localSeconds - fields->tzOffset;
     }
-    fields->tzOffset = have[i];
+
+  found:
+    fields->tzOffset = have[i].tzOffset;
     fields->seconds = fields->localSeconds - fields->tzOffset;
+    Tcl_SetObjRef(fields->tzName, have[i].tzName);
+
     return TCL_OK;
 }
 
@@ -850,19 +2107,14 @@ ConvertLocalToUTCUsingC(
     struct tm timeVal;
     int localErrno;
     int secondOfDay;
-    Tcl_WideInt jsec;
 
     /*
      * Convert the given time to a date.
      */
 
-    jsec = fields->localSeconds + JULIAN_SEC_POSIX_EPOCH;
-    fields->julianDay = (int) (jsec / SECONDS_PER_DAY);
-    secondOfDay = (int)(jsec % SECONDS_PER_DAY);
-    if (secondOfDay < 0) {
-	secondOfDay += SECONDS_PER_DAY;
-	fields->julianDay--;
-    }
+    ClockExtractJDAndSODFromSeconds(fields->julianDay, secondOfDay,
+	fields->localSeconds);
+
     GetGregorianEraYearDay(fields, changeover);
     GetMonthDay(fields);
 
@@ -921,20 +2173,67 @@ ConvertLocalToUTCUsingC(
  *----------------------------------------------------------------------
  */
 
-static int
+int
 ConvertUTCToLocal(
+    void *clientData,	/* Client data of the interpreter */
     Tcl_Interp *interp,		/* Tcl interpreter */
     TclDateFields *fields,	/* Fields of the time */
-    Tcl_Obj *tzdata,		/* Time zone data */
+    Tcl_Obj *timezoneObj,	/* Time zone */
     int changeover)		/* Julian Day of the Gregorian transition */
 {
+    ClockClientData *dataPtr = (ClockClientData *)clientData;
+    Tcl_Obj *tzdata;		/* Time zone data */
     Tcl_Size rowc;			/* Number of rows in tzdata */
     Tcl_Obj **rowv;		/* Pointers to the rows */
+    ClockLastTZOffs * ltzoc = NULL;
+
+    /* fast phase-out for shared GMT-object (don't need to convert UTC 2 UTC) */
+    if (timezoneObj == dataPtr->literals[LIT_GMT]) {
+	fields->localSeconds = fields->seconds;
+	fields->tzOffset = 0;
+	if (dataPtr->gmtTZName == NULL) {
+	    Tcl_Obj *tzName;
+	    tzdata = ClockGetTZData(clientData, interp, timezoneObj);
+	    if ( TclListObjGetElements(interp, tzdata, &rowc, &rowv) != TCL_OK
+	      || Tcl_ListObjIndex(interp, rowv[0], 3, &tzName) != TCL_OK) {
+		return TCL_ERROR;
+	    }
+	    Tcl_SetObjRef(dataPtr->gmtTZName, tzName);
+	}
+	Tcl_SetObjRef(fields->tzName, dataPtr->gmtTZName);
+	return TCL_OK;
+    }
+
+    /*
+     * Check cacheable conversion could be used
+     * (last-period UTC2Local cache within the same TZ and seconds)
+     */
+    for (rowc = 0; rowc < 2; rowc++) {
+	ltzoc = &dataPtr->lastTZOffsCache[rowc];
+	if (timezoneObj != ltzoc->timezoneObj || changeover != ltzoc->changeover) {
+	    ltzoc = NULL;
+	    continue;
+	}
+	if ( fields->seconds >= ltzoc->rangesVal[0]
+	  && fields->seconds <  ltzoc->rangesVal[1]
+	) {
+	    /* the same time zone and offset (UTC time inside the last minute) */
+	    fields->tzOffset = ltzoc->tzOffset;
+	    fields->localSeconds = fields->seconds + fields->tzOffset;
+	    Tcl_SetObjRef(fields->tzName, ltzoc->tzName);
+	    return TCL_OK;
+	}
+    }
 
     /*
      * Unpack the tz data.
      */
 
+    tzdata = ClockGetTZData(clientData, interp, timezoneObj);
+    if (tzdata == NULL) {
+	return TCL_ERROR;
+    }
+
     if (TclListObjGetElements(interp, tzdata, &rowc, &rowv) != TCL_OK) {
 	return TCL_ERROR;
     }
@@ -945,10 +2244,47 @@ ConvertUTCToLocal(
      */
 
     if (rowc == 0) {
-	return ConvertUTCToLocalUsingC(interp, fields, changeover);
+
+	if (ConvertUTCToLocalUsingC(interp, fields, changeover) != TCL_OK) {
+	    return TCL_ERROR;
+	}
+
+	/* signal we need to revalidate TZ epoch next time fields gets used. */
+	fields->flags |= CLF_CTZ;
+
+	/* we cannot cache (ranges unknown yet) */
     } else {
-	return ConvertUTCToLocalUsingTable(interp, fields, rowc, rowv);
+	Tcl_WideInt rangesVal[2];
+
+	if (ConvertUTCToLocalUsingTable(interp, fields, rowc, rowv,
+		rangesVal) != TCL_OK) {
+	    return TCL_ERROR;
+	}
+
+	/* converted using table (TZ isn't :localtime) */
+	fields->flags &= ~CLF_CTZ;
+
+	/* Cache the last conversion */
+	if (ltzoc != NULL) { /* slot was found above */
+	    /* timezoneObj and changeover are the same */
+	    Tcl_SetObjRef(ltzoc->tzName, fields->tzName);
+	} else {
+	    /* no TZ in cache - just move second slot down and use the first one */
+	    ltzoc = &dataPtr->lastTZOffsCache[0];
+	    Tcl_UnsetObjRef(dataPtr->lastTZOffsCache[1].timezoneObj);
+	    Tcl_UnsetObjRef(dataPtr->lastTZOffsCache[1].tzName);
+	    memcpy(&dataPtr->lastTZOffsCache[1], ltzoc, sizeof(*ltzoc));
+	    Tcl_InitObjRef(ltzoc->timezoneObj, timezoneObj);
+	    ltzoc->changeover = changeover;
+	    Tcl_InitObjRef(ltzoc->tzName, fields->tzName);
+	}
+	ltzoc->localSeconds = fields->localSeconds;
+	ltzoc->rangesVal[0] = rangesVal[0];
+	ltzoc->rangesVal[1] = rangesVal[1];
+	ltzoc->tzOffset = fields->tzOffset;
     }
+
+    return TCL_OK;
 }
 
 /*
@@ -975,7 +2311,8 @@ ConvertUTCToLocalUsingTable(
     TclDateFields *fields,	/* Fields of the date */
     Tcl_Size rowc,			/* Number of rows in the conversion table
 				 * (>= 1) */
-    Tcl_Obj *const rowv[])	/* Rows of the conversion table */
+    Tcl_Obj *const rowv[],	/* Rows of the conversion table */
+    Tcl_WideInt *rangesVal)	/* Return bounds for time period */
 {
     Tcl_Obj *row;		/* Row containing the current information */
     Tcl_Size cellc;			/* Count of cells in the row (must be 4) */
@@ -985,7 +2322,7 @@ ConvertUTCToLocalUsingTable(
      * Look up the nearest transition time.
      */
 
-    row = LookupLastTransition(interp, fields->seconds, rowc, rowv);
+    row = LookupLastTransition(interp, fields->seconds, rowc, rowv, rangesVal);
     if (row == NULL ||
 	    TclListObjGetElements(interp, row, &cellc, &cellv) != TCL_OK ||
 	    TclGetIntFromObj(interp, cellv[1], &fields->tzOffset) != TCL_OK) {
@@ -996,8 +2333,7 @@ ConvertUTCToLocalUsingTable(
      * Convert the time.
      */
 
-    fields->tzName = cellv[3];
-    Tcl_IncrRefCount(fields->tzName);
+    Tcl_SetObjRef(fields->tzName, cellv[3]);
     fields->localSeconds = fields->seconds + fields->tzOffset;
     return TCL_OK;
 }
@@ -1030,7 +2366,7 @@ ConvertUTCToLocalUsingC(
     time_t tock;
     struct tm *timeVal;		/* Time after conversion */
     int diff;			/* Time zone diff local-Greenwich */
-    char buffer[16];		/* Buffer for time zone name */
+    char buffer[16], *p;	/* Buffer for time zone name */
 
     /*
      * Use 'localtime' to determine local year, month, day, time of day.
@@ -1067,7 +2403,7 @@ ConvertUTCToLocalUsingC(
      * Convert that value to seconds.
      */
 
-    fields->localSeconds = (((fields->julianDay * (Tcl_WideInt) 24
+    fields->localSeconds = (((fields->julianDay * 24LL
 	    + timeVal->tm_hour) * 60 + timeVal->tm_min) * 60
 	    + timeVal->tm_sec) - JULIAN_SEC_POSIX_EPOCH;
 
@@ -1083,15 +2419,12 @@ ConvertUTCToLocalUsingC(
     } else {
 	*buffer = '+';
     }
-    snprintf(buffer+1, sizeof(buffer) - 1, "%02d", diff / 3600);
-    diff %= 3600;
-    snprintf(buffer+3, sizeof(buffer) - 3, "%02d", diff / 60);
-    diff %= 60;
-    if (diff > 0) {
-	snprintf(buffer+5, sizeof(buffer) - 5, "%02d", diff);
+    TclItoAw(buffer+1, diff / 3600, '0', 2);   diff %= 3600;
+    p = TclItoAw(buffer+3, diff / 60, '0', 2); diff %= 60;
+    if (diff != 0) {
+	p = TclItoAw(buffer+5, diff, '0', 2);
     }
-    fields->tzName = Tcl_NewStringObj(buffer, -1);
-    Tcl_IncrRefCount(fields->tzName);
+    Tcl_SetObjRef(fields->tzName, Tcl_NewStringObj(buffer, p - buffer));
     return TCL_OK;
 }
 
@@ -1109,16 +2442,17 @@ ConvertUTCToLocalUsingC(
  *----------------------------------------------------------------------
  */
 
-static Tcl_Obj *
+Tcl_Obj *
 LookupLastTransition(
     Tcl_Interp *interp,		/* Interpreter for error messages */
     Tcl_WideInt tick,		/* Time from the epoch */
     Tcl_Size rowc,			/* Number of rows of tzdata */
-    Tcl_Obj *const *rowv)	/* Rows in tzdata */
+    Tcl_Obj *const *rowv,	/* Rows in tzdata */
+    Tcl_WideInt *rangesVal)	/* Return bounds for time period */
 {
-    Tcl_Size l, u;
+	Tcl_Size l, u;
     Tcl_Obj *compObj;
-    Tcl_WideInt compVal;
+    Tcl_WideInt compVal, fromVal = LLONG_MIN, toVal = LLONG_MAX;
 
     /*
      * Examine the first row to make sure we're in bounds.
@@ -1134,7 +2468,11 @@ LookupLastTransition(
      * anyway.
      */
 
-    if (tick < compVal) {
+    if (tick < (fromVal = compVal)) {
+	if (rangesVal) {
+	    rangesVal[0] = fromVal;
+	    rangesVal[1] = toVal;
+	}
 	return rowv[0];
     }
 
@@ -1153,10 +2491,17 @@ LookupLastTransition(
 	}
 	if (tick >= compVal) {
 	    l = m;
+	    fromVal = compVal;
 	} else {
 	    u = m-1;
+	    toVal = compVal;
 	}
     }
+
+    if (rangesVal) {
+	rangesVal[0] = fromVal;
+	rangesVal[1] = toVal;
+    }
     return rowv[l];
 }
 
@@ -1187,6 +2532,8 @@ GetYearWeekDay(
     TclDateFields temp;
     int dayOfFiscalYear;
 
+    temp.tzName = NULL;
+
     /*
      * Find the given date, minus three days, plus one year. That date's
      * iso8601 year is an upper bound on the ISO8601 year of the given date.
@@ -1409,7 +2756,7 @@ GetMonthDay(
  *----------------------------------------------------------------------
  */
 
-static void
+void
 GetJulianDayFromEraYearWeekDay(
     TclDateFields *fields,	/* Date to convert */
     int changeover)		/* Julian Day Number of the Gregorian
@@ -1419,6 +2766,8 @@ GetJulianDayFromEraYearWeekDay(
 				 * given year */
     TclDateFields firstWeek;
 
+    firstWeek.tzName = NULL;
+
     /*
      * Find January 4 in the ISO8601 year, which will always be in week 1.
      */
@@ -1460,7 +2809,7 @@ GetJulianDayFromEraYearWeekDay(
  *----------------------------------------------------------------------
  */
 
-static void
+void
 GetJulianDayFromEraYearMonthDay(
     TclDateFields *fields,	/* Date to convert */
     int changeover)		/* Gregorian transition date as a Julian Day */
@@ -1557,6 +2906,61 @@ GetJulianDayFromEraYearMonthDay(
 /*
  *----------------------------------------------------------------------
  *
+ * GetJulianDayFromEraYearDay --
+ *
+ *	Given era, year, and dayOfYear (in TclDateFields), and the
+ *	Gregorian transition date, computes the Julian Day Number.
+ *
+ * Results:
+ *	None.
+ *
+ * Side effects:
+ *	Stores day number in 'julianDay'
+ *
+ *----------------------------------------------------------------------
+ */
+
+
+void
+GetJulianDayFromEraYearDay(
+    TclDateFields *fields,	/* Date to convert */
+    int changeover)		/* Gregorian transition date as a Julian Day */
+{
+    Tcl_WideInt year, ym1;
+
+    /* Get absolute year number from the civil year */
+    if (fields->isBce) {
+	year = 1 - fields->year;
+    } else {
+	year = fields->year;
+    }
+
+    ym1 = year - 1;
+
+    /* Try the Gregorian calendar first. */
+    fields->gregorian = 1;
+    fields->julianDay =
+	1721425
+	+ fields->dayOfYear
+	+ ( 365 * ym1 )
+	+ ( ym1 / 4 )
+	- ( ym1 / 100 )
+	+ ( ym1 / 400 );
+
+    /* If the date is before the Gregorian change, use the Julian calendar. */
+
+    if ( fields->julianDay < changeover ) {
+	fields->gregorian = 0;
+	fields->julianDay =
+	    1721423
+	    + fields->dayOfYear
+	    + ( 365 * ym1 )
+	    + ( ym1 / 4 );
+    }
+}
+/*
+ *----------------------------------------------------------------------
+ *
  * IsGregorianLeapYear --
  *
  *	Tests whether a given year is a leap year, in either Julian or
@@ -1568,7 +2972,7 @@ GetJulianDayFromEraYearMonthDay(
  *----------------------------------------------------------------------
  */
 
-static int
+int
 IsGregorianLeapYear(
     TclDateFields *fields)	/* Date to test */
 {
@@ -1767,14 +3171,14 @@ ClockClicksObjCmd(
 	}
 	break;
     default:
-	Tcl_WrongNumArgs(interp, 1, objv, "?-switch?");
+	Tcl_WrongNumArgs(interp, 0, objv, "clock clicks ?-switch?");
 	return TCL_ERROR;
     }
 
     switch (index) {
     case CLICKS_MILLIS:
 	Tcl_GetTime(&now);
-	clicks = (Tcl_WideInt)now.sec * 1000 + now.usec / 1000;
+	clicks = now.sec * 1000LL + now.usec / 1000;
 	break;
     case CLICKS_NATIVE:
 #ifdef TCL_WIDE_CLICKS
@@ -1821,7 +3225,7 @@ ClockMillisecondsObjCmd(
     Tcl_Obj *timeObj;
 
     if (objc != 1) {
-	Tcl_WrongNumArgs(interp, 1, objv, NULL);
+	Tcl_WrongNumArgs(interp, 0, objv, "clock milliseconds");
 	return TCL_ERROR;
     }
     Tcl_GetTime(&now);
@@ -1857,129 +3261,1295 @@ ClockMicrosecondsObjCmd(
     Tcl_Obj *const *objv)	/* Parameter values */
 {
     if (objc != 1) {
-	Tcl_WrongNumArgs(interp, 1, objv, NULL);
+	Tcl_WrongNumArgs(interp, 0, objv, "clock microseconds");
 	return TCL_ERROR;
     }
     Tcl_SetObjResult(interp, Tcl_NewWideIntObj(TclpGetMicroseconds()));
     return TCL_OK;
 }
 
+static inline void
+ClockInitFmtScnArgs(
+    void *clientData,
+    Tcl_Interp *interp,
+    ClockFmtScnCmdArgs *opts)
+{
+    memset(opts, 0, sizeof(*opts));
+    opts->clientData = clientData;
+    opts->interp = interp;
+}
+
 /*
  *-----------------------------------------------------------------------------
  *
- * ClockParseformatargsObjCmd --
+ * ClockParseFmtScnArgs --
  *
- *	Parses the arguments for [clock format].
+ *	Parses the arguments for sub-commands "scan", "format" and "add".
  *
- * Results:
- *	Returns a standard Tcl result, whose value is a four-element list
- *	comprising the time format, the locale, and the timezone.
+ *	Note:	common options table used here, because for the options often used
+ *		the same literals (objects), so it avoids permanent "recompiling" of
+ *		option object representation to indexType with another table.
  *
- * This function exists because the loop that parses the [clock format]
- * options is a known performance "hot spot", and is implemented in an effort
- * to speed that particular code up.
+ * Results:
+ *	Returns a standard Tcl result, and stores parsed options
+ *	(format, the locale, timezone and base) in structure "opts".
  *
  *-----------------------------------------------------------------------------
  */
 
+#define CLC_FMT_ARGS	(0)
+#define CLC_SCN_ARGS	(1 << 0)
+#define CLC_ADD_ARGS	(1 << 1)
+
 static int
-ClockParseformatargsObjCmd(
-    void *clientData,	/* Client data containing literal pool */
-    Tcl_Interp *interp,		/* Tcl interpreter */
+ClockParseFmtScnArgs(
+    ClockFmtScnCmdArgs *opts,	/* Result vector: format, locale, timezone... */
+    TclDateFields      *date,	/* Extracted date-time corresponding base
+				 * (by scan or add) resp. clockval (by format) */
     int objc,			/* Parameter count */
-    Tcl_Obj *const objv[])	/* Parameter vector */
-{
-    ClockClientData *dataPtr = (ClockClientData *)clientData;
-    Tcl_Obj **litPtr = dataPtr->literals;
-    Tcl_Obj *results[3];	/* Format, locale and timezone */
-#define formatObj results[0]
-#define localeObj results[1]
-#define timezoneObj results[2]
+    Tcl_Obj *const objv[],	/* Parameter vector */
+    int		flags,		/* Flags, differentiates between format, scan, add */
+    const char *syntax		/* Syntax of the current command */
+) {
+    Tcl_Interp	    *interp =  opts->interp;
+    ClockClientData *dataPtr = (ClockClientData *)opts->clientData;
     int gmtFlag = 0;
-    static const char *const options[] = { /* Command line options expected */
-	"-format",	"-gmt",		"-locale",
-	"-timezone",	NULL };
+    static const char *const options[] = {
+	"-base", "-format", "-gmt", "-locale", "-timezone", "-validate", NULL
+    };
     enum optionInd {
-	CLOCK_FORMAT_FORMAT,	CLOCK_FORMAT_GMT,	CLOCK_FORMAT_LOCALE,
-	CLOCK_FORMAT_TIMEZONE
+	CLC_ARGS_BASE, CLC_ARGS_FORMAT, CLC_ARGS_GMT, CLC_ARGS_LOCALE,
+	CLC_ARGS_TIMEZONE, CLC_ARGS_VALIDATE
     };
     int optionIndex;		/* Index of an option. */
     int saw = 0;		/* Flag == 1 if option was seen already. */
-    Tcl_WideInt clockVal;	/* Clock value - just used to parse. */
     int i;
+    Tcl_WideInt baseVal;	/* Base time, expressed in seconds from the Epoch */
 
-    /*
-     * Args consist of a time followed by keyword-value pairs.
-     */
-
-    if (objc < 2 || (objc % 2) != 0) {
-	Tcl_WrongNumArgs(interp, 0, objv,
-		"clock format clockval ?-format string? "
-		"?-gmt boolean? ?-locale LOCALE? ?-timezone ZONE?");
-	Tcl_SetErrorCode(interp, "CLOCK", "wrongNumArgs", (char *)NULL);
-	return TCL_ERROR;
+    if ( flags & (CLC_SCN_ARGS) ) {
+    	/* default flags (from configure) */
+    	opts->flags |= dataPtr->defFlags & (CLF_VALIDATE);
+    } else {
+    	/* clock value (as current base) */
+	opts->baseObj = objv[1];
+	saw |= (1 << CLC_ARGS_BASE);
     }
 
     /*
      * Extract values for the keywords.
      */
 
-    formatObj = litPtr[LIT__DEFAULT_FORMAT];
-    localeObj = litPtr[LIT_C];
-    timezoneObj = litPtr[LIT__NIL];
     for (i = 2; i < objc; i+=2) {
-	if (Tcl_GetIndexFromObj(interp, objv[i], options, "option", 0,
-		&optionIndex) != TCL_OK) {
-	    Tcl_SetErrorCode(interp, "CLOCK", "badOption",
-		    TclGetString(objv[i]), (char *)NULL);
-	    return TCL_ERROR;
+	/* bypass integers (offsets) by "clock add" */
+	if (flags & CLC_ADD_ARGS) {
+	    Tcl_WideInt num;
+	    if (TclGetWideIntFromObj(NULL, objv[i], &num) == TCL_OK) {
+		continue;
+	    }
+	}
+	/* get option */
+	if (Tcl_GetIndexFromObj(interp, objv[i], options,
+	    "option", 0, &optionIndex) != TCL_OK) {
+	    goto badOptionMsg;
+	}
+	/* if already specified */
+	if (saw & (1 << optionIndex)) {
+	    if ( !(flags & CLC_SCN_ARGS)
+	       && optionIndex == CLC_ARGS_BASE) {
+		goto badOptionMsg;
+	    }
+	    Tcl_SetObjResult(interp, Tcl_ObjPrintf(
+		"bad option \"%s\": doubly present",
+		TclGetString(objv[i]))
+	    );
+	    goto badOption;
 	}
 	switch (optionIndex) {
-	case CLOCK_FORMAT_FORMAT:
-	    formatObj = objv[i+1];
+	case CLC_ARGS_FORMAT:
+	    if (flags & CLC_ADD_ARGS) {
+		goto badOptionMsg;
+	    }
+	    opts->formatObj = objv[i+1];
 	    break;
-	case CLOCK_FORMAT_GMT:
+	case CLC_ARGS_GMT:
 	    if (Tcl_GetBooleanFromObj(interp, objv[i+1], &gmtFlag) != TCL_OK){
 		return TCL_ERROR;
 	    }
 	    break;
-	case CLOCK_FORMAT_LOCALE:
-	    localeObj = objv[i+1];
+	case CLC_ARGS_LOCALE:
+	    opts->localeObj = objv[i+1];
+	    break;
+	case CLC_ARGS_TIMEZONE:
+	    opts->timezoneObj = objv[i+1];
+	    break;
+	case CLC_ARGS_BASE:
+	    opts->baseObj = objv[i+1];
 	    break;
-	case CLOCK_FORMAT_TIMEZONE:
-	    timezoneObj = objv[i+1];
+	case CLC_ARGS_VALIDATE:
+	    if ( !(flags & CLC_SCN_ARGS) ) {
+		goto badOptionMsg;
+	    } else {
+		int val;
+		if (Tcl_GetBooleanFromObj(interp, objv[i+1], &val) != TCL_OK) {
+		    return TCL_ERROR;
+		}
+		if (val) {
+		    opts->flags |= CLF_VALIDATE;
+		} else {
+		    opts->flags &= ~CLF_VALIDATE;
+		}
+	    }
 	    break;
 	}
-	saw |= 1 << optionIndex;
+	saw |= (1 << optionIndex);
     }
 
     /*
      * Check options.
      */
 
-    if (TclGetWideIntFromObj(interp, objv[1], &clockVal) != TCL_OK) {
-	return TCL_ERROR;
-    }
-    if ((saw & (1 << CLOCK_FORMAT_GMT))
-	    && (saw & (1 << CLOCK_FORMAT_TIMEZONE))) {
-	Tcl_SetObjResult(interp, litPtr[LIT_CANNOT_USE_GMT_AND_TIMEZONE]);
+    if ((saw & (1 << CLC_ARGS_GMT))
+	    && (saw & (1 << CLC_ARGS_TIMEZONE))) {
+	Tcl_SetObjResult(interp, Tcl_NewStringObj("cannot use -gmt and -timezone in same call", -1));
 	Tcl_SetErrorCode(interp, "CLOCK", "gmtWithTimezone", (char *)NULL);
 	return TCL_ERROR;
     }
     if (gmtFlag) {
-	timezoneObj = litPtr[LIT_GMT];
+	opts->timezoneObj = dataPtr->literals[LIT_GMT];
+    }
+    else
+    /* If time zone not specified use system time zone */
+    if ( opts->timezoneObj == NULL
+      || TclGetString(opts->timezoneObj) == NULL
+      || opts->timezoneObj->length == 0
+    ) {
+	opts->timezoneObj = ClockGetSystemTimeZone(opts->clientData, interp);
+	if (opts->timezoneObj == NULL) {
+	    return TCL_ERROR;
+	}
+    }
+
+    /* Setup timezone (normalize object if needed and load TZ on demand) */
+
+    opts->timezoneObj = ClockSetupTimeZone(opts->clientData, interp, opts->timezoneObj);
+    if (opts->timezoneObj == NULL) {
+	return TCL_ERROR;
+    }
+
+    /* Base (by scan or add) or clock value (by format) */
+
+    if (opts->baseObj != NULL) {
+	Tcl_Obj *baseObj = opts->baseObj;
+	/* bypass integer recognition if looks like option "-now" */
+	if (
+	    (baseObj->length == 4 && baseObj->bytes && *(baseObj->bytes+1) == 'n') ||
+	    TclGetWideIntFromObj(NULL, baseObj, &baseVal) != TCL_OK
+	) {
+
+	    /* we accept "-now" as current date-time */
+	    static const char *const nowOpts[] = {
+		"-now", NULL
+	    };
+	    int idx;
+	    if (Tcl_GetIndexFromObj(NULL, baseObj, nowOpts, "seconds or -now",
+		    TCL_EXACT, &idx) == TCL_OK
+	    ) {
+		goto baseNow;
+	    }
+
+	    Tcl_SetObjResult(interp, Tcl_ObjPrintf(
+		    "expected integer but got \"%s\"",
+		    Tcl_GetString(baseObj)));
+	    Tcl_SetErrorCode(interp, "TCL", "VALUE", "INTEGER", (char *)NULL);
+	    i = 1;
+	    goto badOption;
+	}
+	/*
+	 * Seconds could be an unsigned number that overflowed. Make sure
+	 * that it isn't. Additionally it may be too complex to calculate
+	 * julianday etc (forwards/backwards) by too large/small values, thus
+	 * just let accept a bit shorter values to avoid overflow.
+	 * Note the year is currently an integer, thus avoid to overflow it also.
+	 */
+
+	if ( baseObj->typePtr == &tclBignumType
+	  || baseVal < TCL_MIN_SECONDS || baseVal > TCL_MAX_SECONDS
+	) {
+	    Tcl_SetObjResult(interp, dataPtr->literals[LIT_INTEGER_VALUE_TOO_LARGE]);
+	    return TCL_ERROR;
+	}
+
+    } else {
+
+baseNow:
+	{
+	    Tcl_Time now;
+	    Tcl_GetTime(&now);
+	    baseVal = (Tcl_WideInt) now.sec;
+	}
+    }
+
+    /*
+     * Extract year, month and day from the base time for the parser to use as
+     * defaults
+     */
+
+    /* check base fields already cached (by TZ, last-second cache) */
+    if ( dataPtr->lastBase.timezoneObj == opts->timezoneObj
+      && dataPtr->lastBase.date.seconds == baseVal
+      && (!(dataPtr->lastBase.date.flags & CLF_CTZ)
+	     || dataPtr->lastTZEpoch == TzsetIfNecessary())
+    ) {
+	memcpy(date, &dataPtr->lastBase.date, ClockCacheableDateFieldsSize);
+    } else {
+	/* extact fields from base */
+	date->seconds = baseVal;
+	if (ClockGetDateFields(opts->clientData, interp, date, opts->timezoneObj,
+	      GREGORIAN_CHANGE_DATE) != TCL_OK) { /* TODO - GREGORIAN_CHANGE_DATE should be locale-dependent */
+	    return TCL_ERROR;
+	}
+	/* cache last base */
+	memcpy(&dataPtr->lastBase.date, date, ClockCacheableDateFieldsSize);
+	Tcl_SetObjRef(dataPtr->lastBase.timezoneObj, opts->timezoneObj);
+    }
+
+    return TCL_OK;
+
+badOptionMsg:
+
+    Tcl_SetObjResult(interp, Tcl_ObjPrintf(
+	"bad option \"%s\": must be %s",
+	TclGetString(objv[i]), syntax)
+    );
+
+badOption:
+
+    Tcl_SetErrorCode(interp, "CLOCK", "badOption",
+	    (i < objc) ? Tcl_GetString(objv[i]) : (char *)NULL, (char *)NULL);
+
+    return TCL_ERROR;
+}
+
+/*----------------------------------------------------------------------
+ *
+ * ClockFormatObjCmd -- , clock format --
+ *
+ *	This function is invoked to process the Tcl "clock format" command.
+ *
+ *	Formats a count of seconds since the Posix Epoch as a time of day.
+ *
+ *	The 'clock format' command formats times of day for output.  Refer
+ *	to the user documentation to see what it does.
+ *
+ * Results:
+ *	Returns a standard Tcl result.
+ *
+ * Side effects:
+ *	None.
+ *
+ *----------------------------------------------------------------------
+ */
+
+int
+ClockFormatObjCmd(
+    void *clientData,	/* Client data containing literal pool */
+    Tcl_Interp *interp,		/* Tcl interpreter */
+    int objc,			/* Parameter count */
+    Tcl_Obj *const objv[])	/* Parameter values */
+{
+    ClockClientData *dataPtr = (ClockClientData *)clientData;
+
+    static const char *syntax = "clock format clockval|-now "
+	"?-format string? "
+	"?-gmt boolean? "
+	"?-locale LOCALE? ?-timezone ZONE?";
+    int ret;
+    ClockFmtScnCmdArgs opts;	/* Format, locale, timezone and base */
+    DateFormat	    dateFmt;	/* Common structure used for formatting */
+
+    /* even number of arguments */
+    if ((objc & 1) == 1) {
+	Tcl_WrongNumArgs(interp, 0, objv, syntax);
+	Tcl_SetErrorCode(interp, "CLOCK", "wrongNumArgs", (char *)NULL);
+	return TCL_ERROR;
+    }
+
+    memset(&dateFmt, 0, sizeof(dateFmt));
+
+    /*
+     * Extract values for the keywords.
+     */
+
+    ClockInitFmtScnArgs(clientData, interp, &opts);
+    ret = ClockParseFmtScnArgs(&opts, &dateFmt.date, objc, objv,
+	    CLC_FMT_ARGS, "-format, -gmt, -locale, or -timezone");
+    if (ret != TCL_OK) {
+	goto done;
+    }
+
+    /* Default format */
+    if (opts.formatObj == NULL) {
+	opts.formatObj = dataPtr->literals[LIT__DEFAULT_FORMAT];
+    }
+
+    /* Use compiled version of Format - */
+
+    ret = ClockFormat(&dateFmt, &opts);
+
+done:
+
+    Tcl_UnsetObjRef(dateFmt.date.tzName);
+
+    if (ret != TCL_OK) {
+	return ret;
+    }
+
+    return TCL_OK;
+}
+
+/*----------------------------------------------------------------------
+ *
+ * ClockScanObjCmd -- , clock scan --
+ *
+ *	This function is invoked to process the Tcl "clock scan" command.
+ *
+ *	Inputs a count of seconds since the Posix Epoch as a time of day.
+ *
+ *	The 'clock scan' command scans times of day on input. Refer to the
+ *	user documentation to see what it does.
+ *
+ * Results:
+ *	Returns a standard Tcl result.
+ *
+ * Side effects:
+ *	None.
+ *
+ *----------------------------------------------------------------------
+ */
+
+int
+ClockScanObjCmd(
+    void *clientData,	/* Client data containing literal pool */
+    Tcl_Interp *interp,		/* Tcl interpreter */
+    int objc,			/* Parameter count */
+    Tcl_Obj *const objv[])	/* Parameter values */
+{
+    static const char *syntax = "clock scan string "
+	    "?-base seconds? "
+	    "?-format string? "
+	    "?-gmt boolean? "
+	    "?-locale LOCALE? ?-timezone ZONE? ?-validate boolean?";
+    int ret;
+    ClockFmtScnCmdArgs opts;	/* Format, locale, timezone and base */
+    DateInfo	    yy;		/* Common structure used for parsing */
+    DateInfo	   *info = &yy;
+
+    /* even number of arguments */
+    if ((objc & 1) == 1) {
+	Tcl_WrongNumArgs(interp, 0, objv, syntax);
+	Tcl_SetErrorCode(interp, "CLOCK", "wrongNumArgs", (char *)NULL);
+	return TCL_ERROR;
+    }
+
+    ClockInitDateInfo(&yy);
+
+    /*
+     * Extract values for the keywords.
+     */
+
+    ClockInitFmtScnArgs(clientData, interp, &opts);
+    ret = ClockParseFmtScnArgs(&opts, &yy.date, objc, objv,
+	    CLC_SCN_ARGS, "-base, -format, -gmt, -locale, -timezone or -validate");
+    if (ret != TCL_OK) {
+	goto done;
+    }
+
+    /* seconds are in localSeconds (relative base date), so reset time here */
+    yyHour = yyMinutes = yySeconds = yySecondOfDay = 0; yyMeridian = MER24;
+
+    /* If free scan */
+    if (opts.formatObj == NULL) {
+	/* Use compiled version of FreeScan - */
+
+	/* [SB] TODO: Perhaps someday we'll localize the legacy code. Right now, it's not localized. */
+	if (opts.localeObj != NULL) {
+	    Tcl_SetObjResult(interp,
+		Tcl_NewStringObj("legacy [clock scan] does not support -locale", -1));
+	    Tcl_SetErrorCode(interp, "CLOCK", "flagWithLegacyFormat", (char *)NULL);
+	    ret = TCL_ERROR;
+	    goto done;
+	}
+	ret = ClockFreeScan(&yy, objv[1], &opts);
+    }
+    else {
+	/* Use compiled version of Scan - */
+
+	ret = ClockScan(&yy, objv[1], &opts);
+    }
+
+    if (ret != TCL_OK) {
+	goto done;
+    }
+
+    /*
+     * If no GMT and not free-scan (where valid stage 1 is done in-between),
+     * validate with stage 1 before local time conversion, otherwise it may
+     * adjust date/time tokens to valid values
+     */
+    if ( (opts.flags & CLF_VALIDATE_S1) &&
+	 info->flags & (CLF_ASSEMBLE_SECONDS|CLF_LOCALSEC)
+    ) {
+	ret = ClockValidDate(&yy, &opts, CLF_VALIDATE_S1);
+	if (ret != TCL_OK) {
+	    goto done;
+	}
+    }
+
+    /* Convert date info structure into UTC seconds */
+
+    ret = ClockScanCommit(&yy, &opts);
+    if (ret != TCL_OK) {
+	goto done;
+    }
+
+    /* Apply remaining validation rules, if expected */
+    if ( (opts.flags & CLF_VALIDATE) ) {
+	ret = ClockValidDate(&yy, &opts, opts.flags & CLF_VALIDATE);
+	if (ret != TCL_OK) {
+	    goto done;
+	}
+    }
+
+done:
+
+    Tcl_UnsetObjRef(yy.date.tzName);
+
+    if (ret != TCL_OK) {
+	return ret;
+    }
+
+    Tcl_SetObjResult(interp, Tcl_NewWideIntObj(yy.date.seconds));
+    return TCL_OK;
+}
+
+/*----------------------------------------------------------------------
+ *
+ * ClockScanCommit --
+ *
+ *	Converts date info structure into UTC seconds.
+ *
+ * Results:
+ *	Returns a standard Tcl result.
+ *
+ * Side effects:
+ *	None.
+ *
+ *----------------------------------------------------------------------
+ */
+
+static int
+ClockScanCommit(
+    DateInfo  *info,	/* Clock scan info structure */
+    ClockFmtScnCmdArgs *opts)	/* Format, locale, timezone and base */
+{
+    /* If needed assemble julianDay using year, month, etc. */
+    if (info->flags & CLF_ASSEMBLE_JULIANDAY) {
+	if ((info->flags & CLF_ISO8601WEAK)) {
+	    GetJulianDayFromEraYearWeekDay(&yydate, GREGORIAN_CHANGE_DATE);
+	}
+	else
+	if ( !(info->flags & CLF_DAYOFYEAR) /* no day of year */
+	   || (info->flags & (CLF_DAYOFMONTH|CLF_MONTH)) /* yymmdd over yyddd */
+		== (CLF_DAYOFMONTH|CLF_MONTH)
+	) {
+	    GetJulianDayFromEraYearMonthDay(&yydate, GREGORIAN_CHANGE_DATE);
+	} else {
+	    GetJulianDayFromEraYearDay(&yydate, GREGORIAN_CHANGE_DATE);
+	}
+	info->flags |= CLF_ASSEMBLE_SECONDS;
+	info->flags &= ~CLF_ASSEMBLE_JULIANDAY;
+    }
+
+    /* some overflow checks */
+    if (info->flags & CLF_JULIANDAY) {
+	ClockClientData *dataPtr = (ClockClientData *)opts->clientData;
+	double curJDN = (double)yydate.julianDay
+	    + ((double)yySecondOfDay - SECONDS_PER_DAY/2) / SECONDS_PER_DAY;
+	if (curJDN > dataPtr->maxJDN) {
+	    Tcl_SetObjResult(opts->interp, Tcl_NewStringObj(
+		"requested date too large to represent", -1));
+	    Tcl_SetErrorCode(opts->interp, "CLOCK", "dateTooLarge", (char *)NULL);
+	    return TCL_ERROR;
+	}
+    }
+
+    /* Local seconds to UTC (stored in yydate.seconds) */
+
+    if (info->flags & (CLF_ASSEMBLE_SECONDS)) {
+	yydate.localSeconds =
+	    -210866803200LL
+	    + ( SECONDS_PER_DAY * yydate.julianDay )
+	    + ( yySecondOfDay % SECONDS_PER_DAY );
+    }
+
+    if (info->flags & (CLF_ASSEMBLE_SECONDS|CLF_LOCALSEC)) {
+	if (ConvertLocalToUTC(opts->clientData, opts->interp, &yydate,
+		opts->timezoneObj, GREGORIAN_CHANGE_DATE) != TCL_OK) {
+	    return TCL_ERROR;
+	}
+    }
+
+    /* Increment UTC seconds with relative time */
+
+    yydate.seconds += yyRelSeconds;
+
+    return TCL_OK;
+}
+
+/*----------------------------------------------------------------------
+ *
+ * ClockValidDate --
+ *
+ *	Validate date info structure for wrong data (e. g. out of ranges).
+ *
+ * Results:
+ *	Returns a standard Tcl result.
+ *
+ * Side effects:
+ *	None.
+ *
+ *----------------------------------------------------------------------
+ */
+
+static int
+ClockValidDate(
+    DateInfo  *info,	/* Clock scan info structure */
+    ClockFmtScnCmdArgs *opts,	/* Scan options */
+    int stage)			/* Stage to validate (1, 2 or 3 for both) */
+{
+    const char *errMsg = "", *errCode = "";
+    TclDateFields temp;
+    int tempCpyFlg = 0;
+    ClockClientData *dataPtr = (ClockClientData *)opts->clientData;
+
+    #if 0
+    printf("yyMonth %d, yyDay %d, yyDayOfYear %d, yyHour %d, yyMinutes %d, yySeconds %d, "
+	   "yySecondOfDay %d, sec %d, daySec %d, tzOffset %d\n",
+	  yyMonth, yyDay, yydate.dayOfYear, yyHour, yyMinutes, yySeconds,
+	  yySecondOfDay, (int)yydate.localSeconds, (int)(yydate.localSeconds % SECONDS_PER_DAY),
+	  yydate.tzOffset);
+    #endif
+
+    if (!(stage & CLF_VALIDATE_S1) || !(opts->flags & CLF_VALIDATE_S1)) {
+	goto stage_2;
+    }
+    opts->flags &= ~CLF_VALIDATE_S1; /* stage 1 is done */
+
+    /* first year (used later in hath / daysInPriorMonths) */
+    if ((info->flags & (CLF_YEAR|CLF_ISO8601YEAR))) {
+	if ((info->flags & CLF_ISO8601YEAR)) {
+	    if ( yydate.iso8601Year < dataPtr->validMinYear
+	      || yydate.iso8601Year > dataPtr->validMaxYear ) {
+		errMsg = "invalid iso year"; errCode = "iso year"; goto error;
+	    }
+	}
+	if (info->flags & CLF_YEAR) {
+	    if ( yyYear < dataPtr->validMinYear
+	      || yyYear > dataPtr->validMaxYear ) {
+		errMsg = "invalid year"; errCode = "year"; goto error;
+	    }
+	} else if ((info->flags & CLF_ISO8601YEAR)) {
+	    yyYear = yydate.iso8601Year; /* used to recognize leap */
+	}
+	if ((info->flags & (CLF_ISO8601YEAR|CLF_YEAR))
+		== (CLF_ISO8601YEAR|CLF_YEAR)) {
+	    if (yyYear != yydate.iso8601Year) {
+		errMsg = "ambiguous year"; errCode = "year"; goto error;
+	    }
+	}
+    }
+    /* and month (used later in hath) */
+    if (info->flags & CLF_MONTH) {
+	if ( yyMonth < 1 || yyMonth > 12 ) {
+	    errMsg = "invalid month"; errCode = "month"; goto error;
+	}
+    }
+    /* day of month */
+    if (info->flags & (CLF_DAYOFMONTH|CLF_DAYOFWEEK)) {
+	if ( yyDay < 1 || yyDay > 31 ) {
+	    errMsg = "invalid day"; errCode = "day"; goto error;
+	}
+	else
+	if ( (info->flags & CLF_MONTH) ) {
+	    const int *h = hath[IsGregorianLeapYear(&yydate)];
+	    if ( yyDay > h[yyMonth-1] ) {
+		errMsg = "invalid day"; goto error;
+	    }
+	}
+    }
+    if (info->flags & CLF_DAYOFYEAR) {
+	if ( yydate.dayOfYear < 1
+	  || yydate.dayOfYear > daysInPriorMonths[IsGregorianLeapYear(&yydate)][12] ) {
+	    errMsg = "invalid day of year"; errCode = "day of year"; goto error;
+	}
+    }
+
+    /* mmdd !~ ddd */
+    if ((info->flags & (CLF_DAYOFYEAR|CLF_DAYOFMONTH|CLF_MONTH))
+		== (CLF_DAYOFYEAR|CLF_DAYOFMONTH|CLF_MONTH)) {
+	if (!tempCpyFlg) {
+	    memcpy(&temp, &yydate, sizeof(temp));
+	    tempCpyFlg = 1;
+	}
+	GetJulianDayFromEraYearDay(&temp, GREGORIAN_CHANGE_DATE);
+	if (temp.julianDay != yydate.julianDay) {
+	    errMsg = "ambiguous day"; errCode = "day"; goto error;
+	}
+    }
+
+    if (info->flags & CLF_TIME) {
+	/* hour */
+	if ( yyHour < 0 || yyHour > ((yyMeridian == MER24) ? 23 : 12) ) {
+	    errMsg = "invalid time (hour)"; errCode = "hour"; goto error;
+	}
+	/* minutes */
+	if ( yyMinutes < 0 || yyMinutes > 59 ) {
+	    errMsg = "invalid time (minutes)"; errCode = "minutes"; goto error;
+	}
+	/* oldscan could return secondOfDay (parsedTime) -1 by invalid time (ex.: 25:00:00) */
+	if ( yySeconds < 0 || yySeconds > 59 || yySecondOfDay <= -1 ) {
+	    errMsg = "invalid time"; errCode = "seconds"; goto error;
+	}
+    }
+
+    if (!(stage & CLF_VALIDATE_S2) || !(opts->flags & CLF_VALIDATE_S2)) {
+	return TCL_OK;
+    }
+    opts->flags &= ~CLF_VALIDATE_S2; /* stage 2 is done */
+
+    /*
+     * Further tests expected ready calculated julianDay (inclusive relative),
+     * and time-zone conversion (local to UTC time).
+     */
+  stage_2:
+
+    /* time, regarding the modifications by the time-zone (looks for given time
+     * in between DST-time hole, so does not exist in this time-zone) */
+    if (info->flags & CLF_TIME) {
+	/*
+	 * we don't need to do the backwards time-conversion (UTC to local) and
+	 * compare results, because the after conversion (local to UTC) we
+	 * should have valid localSeconds (was not invalidated to TCL_INV_SECONDS),
+	 * so if it was invalidated - invalid time, outside the time-zone (in DST-hole)
+	 */
+	if ( yydate.localSeconds == TCL_INV_SECONDS ) {
+	    errMsg = "invalid time (does not exist in this time-zone)";
+	    errCode = "out-of-time"; goto error;
+	}
+    }
+
+    /* day of week */
+    if (info->flags & CLF_DAYOFWEEK) {
+	if (!tempCpyFlg) {
+	    memcpy(&temp, &yydate, sizeof(temp));
+	    tempCpyFlg = 1;
+	}
+	GetYearWeekDay(&temp, GREGORIAN_CHANGE_DATE);
+	if (temp.dayOfWeek != yyDayOfWeek) {
+	    errMsg = "invalid day of week"; errCode = "day of week"; goto error;
+	}
+    }
+
+    return TCL_OK;
+
+  error:
+    Tcl_SetObjResult(opts->interp,
+	Tcl_ObjPrintf("unable to convert input string: %s", errMsg));
+    Tcl_SetErrorCode(opts->interp, "CLOCK", "invInpStr", errCode, (char *)NULL);
+    return TCL_ERROR;
+}
+
+/*----------------------------------------------------------------------
+ *
+ * ClockFreeScan --
+ *
+ *	Used by ClockScanObjCmd for free scanning without format.
+ *
+ * Results:
+ *	Returns a standard Tcl result.
+ *
+ * Side effects:
+ *	None.
+ *
+ *----------------------------------------------------------------------
+ */
+
+int
+ClockFreeScan(
+    DateInfo	       *info,	/* Date fields used for parsing & converting
+				 * simultaneously a yy-parse structure of the
+				 * TclClockFreeScan */
+    Tcl_Obj *strObj,		/* String containing the time to scan */
+    ClockFmtScnCmdArgs *opts)	/* Command options */
+{
+    Tcl_Interp	    *interp =  opts->interp;
+    ClockClientData *dataPtr = (ClockClientData *)opts->clientData;
+
+    int ret = TCL_ERROR;
+
+    /*
+     * Parse the date. The parser will fill a structure "info" with date,
+     * time, time zone, relative month/day/seconds, relative weekday, ordinal
+     * month.
+     * Notice that many yy-defines point to values in the "info" or "date"
+     * structure, e. g. yySecondOfDay -> info->date.secondOfDay or
+     *			yyMonth -> info->date.month (same as yydate.month)
+     */
+    yyInput = Tcl_GetString(strObj);
+
+    if (TclClockFreeScan(interp, info) != TCL_OK) {
+	Tcl_Obj *msg;
+	TclNewObj(msg);
+	Tcl_AppendPrintfToObj(msg, "unable to convert date-time string \"%s\": %s",
+	    Tcl_GetString(strObj), TclGetString(Tcl_GetObjResult(interp)));
+	Tcl_SetObjResult(interp, msg);
+	goto done;
+    }
+
+    /*
+     * If the caller supplied a date in the string, update the date with
+     * the value. If the caller didn't specify a time with the date, default to
+     * midnight.
+     */
+
+    if (info->flags & CLF_YEAR) {
+	if (yyYear < 100) {
+	    if (yyYear >= dataPtr->yearOfCenturySwitch) {
+		yyYear -= 100;
+	    }
+	    yyYear += dataPtr->currentYearCentury;
+	}
+	yydate.isBce = 0;
+	info->flags |= CLF_ASSEMBLE_JULIANDAY|CLF_ASSEMBLE_SECONDS;
+    }
+
+    /*
+     * If the caller supplied a time zone in the string, make it into a time
+     * zone indicator of +-hhmm and setup this time zone.
+     */
+
+    if (info->flags & CLF_ZONE) {
+	if (yyTimezone || !yyDSTmode) {
+	    /* Real time zone from numeric zone */
+	    Tcl_Obj *tzObjStor = NULL;
+	    int minEast = -yyTimezone;
+	    int dstFlag = 1 - yyDSTmode;
+	    tzObjStor = ClockFormatNumericTimeZone(
+				60 * minEast + 3600 * dstFlag);
+	    Tcl_IncrRefCount(tzObjStor);
+
+	    opts->timezoneObj = ClockSetupTimeZone(dataPtr, interp, tzObjStor);
+
+	    Tcl_DecrRefCount(tzObjStor);
+	} else {
+	    /* simplest case - GMT / UTC */
+	    opts->timezoneObj = ClockSetupTimeZone(dataPtr, interp,
+		dataPtr->literals[LIT_GMT]);
+	}
+	if (opts->timezoneObj == NULL) {
+	    goto done;
+	}
+
+	// Tcl_SetObjRef(yydate.tzName, opts->timezoneObj);
+
+	info->flags |= CLF_ASSEMBLE_SECONDS;
+    }
+
+    /*
+     * For freescan apply validation rules (stage 1) before mixed with
+     * relative time (otherwise always valid recalculated date & time).
+     */
+    if ( (opts->flags & CLF_VALIDATE) ) {
+	if (ClockValidDate(info, opts, CLF_VALIDATE_S1) != TCL_OK) {
+	    goto done;
+	}
+    }
+
+    /*
+     * Assemble date, time, zone into seconds-from-epoch
+     */
+
+    if ((info->flags & (CLF_TIME|CLF_HAVEDATE)) == CLF_HAVEDATE) {
+	yySecondOfDay = 0;
+	info->flags |= CLF_ASSEMBLE_SECONDS;
+    }
+    else
+    if (info->flags & CLF_TIME) {
+	yySecondOfDay = ToSeconds(yyHour, yyMinutes,
+			    yySeconds, yyMeridian);
+	info->flags |= CLF_ASSEMBLE_SECONDS;
+    }
+    else
+    if ( (info->flags & (CLF_DAYOFWEEK|CLF_HAVEDATE)) == CLF_DAYOFWEEK
+	    || (info->flags & CLF_ORDINALMONTH)
+	    || ( (info->flags & CLF_RELCONV)
+		&& ( yyRelMonth != 0
+		     || yyRelDay != 0 ) )
+    ) {
+	yySecondOfDay = 0;
+	info->flags |= CLF_ASSEMBLE_SECONDS;
+    }
+    else {
+	yySecondOfDay = yydate.localSeconds % SECONDS_PER_DAY;
+    }
+
+    /*
+     * Do relative times
+     */
+
+    ret = ClockCalcRelTime(info);
+
+    /* Free scanning completed - date ready */
+
+done:
+
+    return ret;
+}
+
+/*----------------------------------------------------------------------
+ *
+ * ClockCalcRelTime --
+ *
+ *	Used for calculating of relative times.
+ *
+ * Results:
+ *	Returns a standard Tcl result.
+ *
+ * Side effects:
+ *	None.
+ *
+ *----------------------------------------------------------------------
+ */
+int
+ClockCalcRelTime(
+    DateInfo	       *info)	/* Date fields used for converting */
+{
+
+    int prevDayOfWeek = yyDayOfWeek;	/* preserve unchanged day of week */
+
+    /*
+     * Because some calculations require in-between conversion of the
+     * julian day, we can repeat this processing multiple times
+     */
+repeat_rel:
+
+    if (info->flags & CLF_RELCONV) {
+
+	/*
+	 * Relative conversion normally possible in UTC time only, because
+	 * of possible wrong local time increment if ignores in-between DST-hole.
+	 * (see test-cases clock-34.53, clock-34.54).
+	 * So increment date in julianDay, but time inside day in UTC (seconds).
+	 */
+
+	/* add months (or years in months) */
+
+	if (yyRelMonth != 0) {
+	    int m, h;
+
+	    /* if needed extract year, month, etc. again */
+	    if (info->flags & CLF_ASSEMBLE_DATE) {
+		GetGregorianEraYearDay(&yydate, GREGORIAN_CHANGE_DATE);
+		GetMonthDay(&yydate);
+		GetYearWeekDay(&yydate, GREGORIAN_CHANGE_DATE);
+		info->flags &= ~CLF_ASSEMBLE_DATE;
+	    }
+
+	    /* add the requisite number of months */
+	    yyMonth += yyRelMonth - 1;
+	    yyYear += yyMonth / 12;
+	    m = yyMonth % 12;
+	    /* compiler fix for negative offs - wrap y, m = (0, -1) -> (-1, 11) */
+	    if (m < 0) {
+		yyYear--;
+		m = 12 + m;
+	    }
+	    yyMonth = m + 1;
+
+	    /* if the day doesn't exist in the current month, repair it */
+	    h = hath[IsGregorianLeapYear(&yydate)][m];
+	    if (yyDay > h) {
+		yyDay = h;
+	    }
+
+	    /* on demand (lazy) assemble julianDay using new year, month, etc. */
+	    info->flags |= CLF_ASSEMBLE_JULIANDAY|CLF_ASSEMBLE_SECONDS;
+
+	    yyRelMonth = 0;
+	}
+
+	/* add days (or other parts aligned to days) */
+	if (yyRelDay) {
+
+	    /* assemble julianDay using new year, month, etc. */
+	    if (info->flags & CLF_ASSEMBLE_JULIANDAY) {
+		GetJulianDayFromEraYearMonthDay(&yydate, GREGORIAN_CHANGE_DATE);
+		info->flags &= ~CLF_ASSEMBLE_JULIANDAY;
+	    }
+	    yydate.julianDay += yyRelDay;
+
+	    /* julianDay was changed, on demand (lazy) extract year, month, etc. again */
+	    info->flags |= CLF_ASSEMBLE_DATE|CLF_ASSEMBLE_SECONDS;
+
+	    yyRelDay = 0;
+	}
+
+	/* relative time (seconds), if exceeds current date, do the day conversion and
+	 * leave rest of the increment in yyRelSeconds to add it hereafter in UTC seconds */
+	if (yyRelSeconds) {
+	    Tcl_WideInt newSecs = yySecondOfDay + yyRelSeconds;
+
+	    /* if seconds increment outside of current date, increment day */
+	    if (newSecs / SECONDS_PER_DAY != yySecondOfDay / SECONDS_PER_DAY) {
+
+		yyRelDay += newSecs / SECONDS_PER_DAY;
+		yySecondOfDay = 0;
+		yyRelSeconds = newSecs % SECONDS_PER_DAY;
+
+		goto repeat_rel;
+	    }
+	}
+
+	info->flags &= ~CLF_RELCONV;
     }
 
     /*
-     * Return options as a list.
+     * Do relative (ordinal) month
      */
 
-    Tcl_SetObjResult(interp, Tcl_NewListObj(3, results));
+    if (info->flags & CLF_ORDINALMONTH) {
+	int monthDiff;
+
+	/* if needed extract year, month, etc. again */
+	if (info->flags & CLF_ASSEMBLE_DATE) {
+	    GetGregorianEraYearDay(&yydate, GREGORIAN_CHANGE_DATE);
+	    GetMonthDay(&yydate);
+	    GetYearWeekDay(&yydate, GREGORIAN_CHANGE_DATE);
+	    info->flags &= ~CLF_ASSEMBLE_DATE;
+	}
+
+	if (yyMonthOrdinalIncr > 0) {
+	    monthDiff = yyMonthOrdinal - yyMonth;
+	    if (monthDiff <= 0) {
+		monthDiff += 12;
+	    }
+	    yyMonthOrdinalIncr--;
+	} else {
+	    monthDiff = yyMonth - yyMonthOrdinal;
+	    if (monthDiff >= 0) {
+		monthDiff -= 12;
+	    }
+	    yyMonthOrdinalIncr++;
+	}
+
+	/* process it further via relative times */
+	yyYear += yyMonthOrdinalIncr;
+	yyRelMonth += monthDiff;
+	info->flags &= ~CLF_ORDINALMONTH;
+	info->flags |= CLF_RELCONV|CLF_ASSEMBLE_JULIANDAY|CLF_ASSEMBLE_SECONDS;
+
+	goto repeat_rel;
+    }
+
+    /*
+     * Do relative weekday
+     */
+
+    if ((info->flags & (CLF_DAYOFWEEK|CLF_HAVEDATE)) == CLF_DAYOFWEEK) {
+
+	/* restore scanned day of week */
+	yyDayOfWeek = prevDayOfWeek;
+
+	/* if needed assemble julianDay now */
+	if (info->flags & CLF_ASSEMBLE_JULIANDAY) {
+	    GetJulianDayFromEraYearMonthDay(&yydate, GREGORIAN_CHANGE_DATE);
+	    info->flags &= ~CLF_ASSEMBLE_JULIANDAY;
+	}
+
+	yydate.isBce = 0;
+	yydate.julianDay = WeekdayOnOrBefore(yyDayOfWeek, yydate.julianDay + 6)
+		    + 7 * yyDayOrdinal;
+	if (yyDayOrdinal > 0) {
+	    yydate.julianDay -= 7;
+	}
+	info->flags |= CLF_ASSEMBLE_DATE|CLF_ASSEMBLE_SECONDS;
+    }
+
     return TCL_OK;
+}
 
-#undef timezoneObj
-#undef localeObj
-#undef formatObj
+
+/*----------------------------------------------------------------------
+ *
+ * ClockWeekdaysOffs --
+ *
+ *	Get offset in days for the number of week days corresponding the
+ *	given day of week (skipping Saturdays and Sundays).
+ *
+ *
+ * Results:
+ *	Returns a day increment adjusted the given weekdays
+ *
+ *----------------------------------------------------------------------
+ */
+
+static inline int
+ClockWeekdaysOffs(
+    int dayOfWeek,
+    int offs)
+{
+    int weeks, resDayOfWeek;
+
+    /* offset in days */
+    weeks = offs / 5;
+    offs = offs % 5;
+    /* compiler fix for negative offs - wrap (0, -1) -> (-1, 4) */
+    if (offs < 0) {
+	weeks--;
+	offs = 5 + offs;
+    }
+    offs += 7 * weeks;
+
+    /* resulting day of week */
+    {
+	int day = (offs % 7);
+	/* compiler fix for negative offs - wrap (0, -1) -> (-1, 6) */
+	if (day < 0) {
+	    day = 7 + day;
+	}
+	resDayOfWeek = dayOfWeek + day;
+    }
+
+    /* adjust if we start from a weekend */
+    if (dayOfWeek > 5) {
+	int adj = 5 - dayOfWeek;
+	offs += adj;
+	resDayOfWeek += adj;
+    }
+
+    /* adjust if we end up on a weekend */
+    if (resDayOfWeek > 5) {
+       offs += 2;
+    }
+
+    return offs;
+}
+
+
+
+/*----------------------------------------------------------------------
+ *
+ * ClockAddObjCmd -- , clock add --
+ *
+ *	Adds an offset to a given time.
+ *
+ *	Refer to the user documentation to see what it exactly does.
+ *
+ * Syntax:
+ *   clock add clockval ?count unit?... ?-option value?
+ *
+ * Parameters:
+ *   clockval -- Starting time value
+ *   count -- Amount of a unit of time to add
+ *   unit -- Unit of time to add, must be one of:
+ *	     years year months month weeks week
+ *	     days day hours hour minutes minute
+ *	     seconds second
+ *
+ * Options:
+ *   -gmt BOOLEAN
+ *	 Flag synonymous with '-timezone :GMT'
+ *   -timezone ZONE
+ *	 Name of the time zone in which calculations are to be done.
+ *   -locale NAME
+ *	 Name of the locale in which calculations are to be done.
+ *	 Used to determine the Gregorian change date.
+ *
+ * Results:
+ *	Returns a standard Tcl result with the given time adjusted
+ *	by the given offset(s) in order.
+ *
+ * Notes:
+ *   It is possible that adding a number of months or years will adjust the
+ *   day of the month as well.	For instance, the time at one month after
+ *   31 January is either 28 or 29 February, because February has fewer
+ *   than 31 days.
+ *
+ *----------------------------------------------------------------------
+ */
+
+int
+ClockAddObjCmd(
+    void *clientData,	/* Client data containing literal pool */
+    Tcl_Interp *interp,		/* Tcl interpreter */
+    int objc,			/* Parameter count */
+    Tcl_Obj *const objv[])	/* Parameter values */
+{
+    static const char *syntax = "clock add clockval|-now ?number units?..."
+	"?-gmt boolean? "
+	"?-locale LOCALE? ?-timezone ZONE?";
+    ClockClientData *dataPtr = (ClockClientData *)clientData;
+    int ret;
+    ClockFmtScnCmdArgs opts;	/* Format, locale, timezone and base */
+    DateInfo	    yy;		/* Common structure used for parsing */
+    DateInfo	   *info = &yy;
+
+    /* add "week" to units also (because otherwise ambiguous) */
+    static const char *const units[] = {
+	"years",	"months",	    "week",	    "weeks",
+	"days",		"weekdays",
+	"hours",	"minutes",	    "seconds",
+	NULL
+    };
+    enum unitInd {
+	CLC_ADD_YEARS,	CLC_ADD_MONTHS,	    CLC_ADD_WEEK,   CLC_ADD_WEEKS,
+	CLC_ADD_DAYS,	CLC_ADD_WEEKDAYS,
+	CLC_ADD_HOURS,	CLC_ADD_MINUTES,    CLC_ADD_SECONDS
+    };
+    int unitIndex;		/* Index of an option. */
+    int i;
+    Tcl_WideInt offs;
+
+    /* even number of arguments */
+    if ((objc & 1) == 1) {
+	Tcl_WrongNumArgs(interp, 0, objv, syntax);
+	Tcl_SetErrorCode(interp, "CLOCK", "wrongNumArgs", (char *)NULL);
+	return TCL_ERROR;
+    }
+
+    ClockInitDateInfo(&yy);
+
+    /*
+     * Extract values for the keywords.
+     */
+
+    ClockInitFmtScnArgs(clientData, interp, &opts);
+    ret = ClockParseFmtScnArgs(&opts, &yy.date, objc, objv,
+	    CLC_ADD_ARGS, "-gmt, -locale, or -timezone");
+    if (ret != TCL_OK) {
+	goto done;
+    }
+
+    /* time together as seconds of the day */
+    yySecondOfDay = yySeconds = yydate.localSeconds % SECONDS_PER_DAY;
+    /* seconds are in localSeconds (relative base date), so reset time here */
+    yyHour = 0; yyMinutes = 0; yyMeridian = MER24;
+
+    ret = TCL_ERROR;
+
+    /*
+     * Find each offset and process date increment
+     */
+
+    for (i = 2; i < objc; i+=2) {
+	/* bypass not integers (options, allready processed above in ClockParseFmtScnArgs) */
+	if (TclGetWideIntFromObj(NULL, objv[i], &offs) != TCL_OK) {
+	    continue;
+	}
+	/* get unit */
+	if (Tcl_GetIndexFromObj(interp, objv[i+1], units, "unit", 0,
+		&unitIndex) != TCL_OK) {
+	    goto done;
+	}
+	if (objv[i]->typePtr == &tclBignumType
+	    || offs > (unitIndex < CLC_ADD_HOURS ? 0x7fffffff : TCL_MAX_SECONDS)
+	    || offs < (unitIndex < CLC_ADD_HOURS ? -0x7fffffff : TCL_MIN_SECONDS)
+	) {
+	    Tcl_SetObjResult(interp, dataPtr->literals[LIT_INTEGER_VALUE_TOO_LARGE]);
+	    goto done;
+	}
+
+	/* nothing to do if zero quantity */
+	if (!offs) {
+	    continue;
+	}
+
+	/* if in-between conversion needed (already have relative date/time),
+	 * correct date info, because the date may be changed,
+	 * so refresh it now */
+
+	if ( (info->flags & CLF_RELCONV)
+	  && ( unitIndex == CLC_ADD_WEEKDAYS
+	    /* some months can be shorter as another */
+	    || yyRelMonth || yyRelDay
+	    /* day changed */
+	    || yySeconds + yyRelSeconds > SECONDS_PER_DAY
+	    || yySeconds + yyRelSeconds < 0
+	  )
+	) {
+	    if (ClockCalcRelTime(info) != TCL_OK) {
+		goto done;
+	    }
+	}
+
+	/* process increment by offset + unit */
+	info->flags |= CLF_RELCONV;
+	switch (unitIndex) {
+	case CLC_ADD_YEARS:
+	    yyRelMonth += offs * 12;
+	    break;
+	case CLC_ADD_MONTHS:
+	    yyRelMonth += offs;
+	    break;
+	case CLC_ADD_WEEK:
+	case CLC_ADD_WEEKS:
+	    yyRelDay += offs * 7;
+	    break;
+	case CLC_ADD_DAYS:
+	    yyRelDay += offs;
+	    break;
+	case CLC_ADD_WEEKDAYS:
+	    /* add number of week days (skipping Saturdays and Sundays)
+	     * to a relative days value. */
+	    offs = ClockWeekdaysOffs(yy.date.dayOfWeek, offs);
+	    yyRelDay += offs;
+	    break;
+	case CLC_ADD_HOURS:
+	    yyRelSeconds += offs * 60 * 60;
+	    break;
+	case CLC_ADD_MINUTES:
+	    yyRelSeconds += offs * 60;
+	    break;
+	case CLC_ADD_SECONDS:
+	    yyRelSeconds += offs;
+	    break;
+	}
+    }
+
+    /*
+     * Do relative times (if not yet already processed interim):
+     */
+
+    if (info->flags & CLF_RELCONV) {
+	if (ClockCalcRelTime(info) != TCL_OK) {
+	    goto done;
+	}
+    }
+
+    /* Convert date info structure into UTC seconds */
+
+    ret = ClockScanCommit(&yy, &opts);
+
+done:
+
+    Tcl_UnsetObjRef(yy.date.tzName);
+
+    if (ret != TCL_OK) {
+	return ret;
+    }
+
+    Tcl_SetObjResult(interp, Tcl_NewWideIntObj(yy.date.seconds));
+    return TCL_OK;
 }
 
 /*----------------------------------------------------------------------
@@ -2011,7 +4581,7 @@ ClockSecondsObjCmd(
     Tcl_Obj *timeObj;
 
     if (objc != 1) {
-	Tcl_WrongNumArgs(interp, 1, objv, NULL);
+	Tcl_WrongNumArgs(interp, 0, objv, "clock seconds");
 	return TCL_ERROR;
     }
     Tcl_GetTime(&now);
@@ -2024,6 +4594,76 @@ ClockSecondsObjCmd(
 /*
  *----------------------------------------------------------------------
  *
+ * ClockSafeCatchCmd --
+ *
+ *	Same as "::catch" command but avoids overwriting of interp state.
+ *
+ *	See [554117edde] for more info (and proper solution).
+ *
+ *----------------------------------------------------------------------
+ */
+int
+ClockSafeCatchCmd(
+    TCL_UNUSED(void *),
+    Tcl_Interp *interp,
+    int objc,
+    Tcl_Obj *const objv[])
+{
+    typedef struct {
+        int status;			/* return code status */
+        int flags;			/* Each remaining field saves the */
+        int returnLevel;		/* corresponding field of the Interp */
+        int returnCode;			/* struct. These fields taken together are */
+        Tcl_Obj *errorInfo;		/* the "state" of the interp. */
+        Tcl_Obj *errorCode;
+        Tcl_Obj *returnOpts;
+        Tcl_Obj *objResult;
+        Tcl_Obj *errorStack;
+        int resetErrorStack;
+    } InterpState;
+
+    Interp *iPtr = (Interp *)interp;
+    int ret, flags = 0;
+    InterpState *statePtr;
+
+    if (objc == 1) {
+	/* wrong # args : */
+	return Tcl_CatchObjCmd(NULL, interp, objc, objv);
+    }
+
+    statePtr = (InterpState *)Tcl_SaveInterpState(interp, 0);
+    if (!statePtr->errorInfo) {
+	/* todo: avoid traced get of errorInfo here */
+	Tcl_InitObjRef(statePtr->errorInfo,
+		Tcl_ObjGetVar2(interp, iPtr->eiVar, NULL, 0));
+	flags |= ERR_LEGACY_COPY;
+    }
+    if (!statePtr->errorCode) {
+	/* todo: avoid traced get of errorCode here */
+	Tcl_InitObjRef(statePtr->errorCode,
+		Tcl_ObjGetVar2(interp, iPtr->ecVar, NULL, 0));
+	flags |= ERR_LEGACY_COPY;
+    }
+
+    /* original catch */
+    ret = Tcl_CatchObjCmd(NULL, interp, objc, objv);
+
+    if (ret == TCL_ERROR) {
+	Tcl_DiscardInterpState((Tcl_InterpState)statePtr);
+	return TCL_ERROR;
+    }
+    /* overwrite result in state with catch result */
+    Tcl_SetObjRef(statePtr->objResult, Tcl_GetObjResult(interp));
+    /* set result (together with restore state) to interpreter */
+    (void) Tcl_RestoreInterpState(interp, (Tcl_InterpState)statePtr);
+    /* todo: unless ERR_LEGACY_COPY not set in restore (branch [bug-554117edde] not merged yet) */
+    iPtr->flags |= (flags & ERR_LEGACY_COPY);
+    return ret;
+}
+
+/*
+ *----------------------------------------------------------------------
+ *
  * TzsetIfNecessary --
  *
  *	Calls the tzset() library function if the contents of the TZ
@@ -2047,12 +4687,13 @@ ClockSecondsObjCmd(
 #define wcscpy strcpy
 #endif
 
-static void
+static size_t
 TzsetIfNecessary(void)
 {
     static WCHAR* tzWas = (WCHAR *)INT2PTR(-1);	 /* Previous value of TZ, protected by
 					  * clockMutex. */
     static long long tzLastRefresh = 0;	 /* Used for latency before next refresh */
+    static size_t tzWasEpoch = 0;        /* Epoch, signals that TZ changed */
     static size_t tzEnvEpoch = 0;        /* Last env epoch, for faster signaling,
 					    that TZ changed via TCL */
     const WCHAR *tzIsNow;		 /* Current value of TZ */
@@ -2065,14 +4706,18 @@ TzsetIfNecessary(void)
     Tcl_Time now;
     Tcl_GetTime(&now);
     if (now.sec == tzLastRefresh && tzEnvEpoch == TclEnvEpoch) {
-	return;
+	return tzWasEpoch;
     }
 
     tzEnvEpoch = TclEnvEpoch;
     tzLastRefresh = now.sec;
 
+    /* check in lock */
     Tcl_MutexLock(&clockMutex);
-    tzIsNow = getenv("TZ");
+    tzIsNow = getenv("TCL_TZ");
+    if (tzIsNow == NULL) {
+	tzIsNow = getenv("TZ");
+    }
     if (tzIsNow != NULL && (tzWas == NULL || tzWas == (WCHAR *)INT2PTR(-1)
 	    || wcscmp(tzIsNow, tzWas) != 0)) {
 	tzset();
@@ -2081,44 +4726,18 @@ TzsetIfNecessary(void)
 	}
 	tzWas = (WCHAR *)Tcl_Alloc(sizeof(WCHAR) * (wcslen(tzIsNow) + 1));
 	wcscpy(tzWas, tzIsNow);
+	tzWasEpoch++;
     } else if (tzIsNow == NULL && tzWas != NULL) {
 	tzset();
 	if (tzWas != (WCHAR *)INT2PTR(-1)) {
 	    Tcl_Free(tzWas);
 	}
 	tzWas = NULL;
+	tzWasEpoch++;
     }
     Tcl_MutexUnlock(&clockMutex);
-}
-
-/*
- *----------------------------------------------------------------------
- *
- * ClockDeleteCmdProc --
- *
- *	Remove a reference to the clock client data, and clean up memory
- *	when it's all gone.
- *
- * Results:
- *	None.
- *
- *----------------------------------------------------------------------
- */
-
-static void
-ClockDeleteCmdProc(
-    void *clientData)	/* Opaque pointer to the client data */
-{
-    ClockClientData *data = (ClockClientData *)clientData;
-    int i;
 
-    if (data->refCount-- <= 1) {
-	for (i = 0; i < LIT__END; ++i) {
-	    Tcl_DecrRefCount(data->literals[i]);
-	}
-	Tcl_Free(data->literals);
-	Tcl_Free(data);
-    }
+    return tzWasEpoch;
 }
 
 /*
diff --git a/generic/tclClockFmt.c b/generic/tclClockFmt.c
new file mode 100644
index 0000000..d2175e6
--- /dev/null
+++ b/generic/tclClockFmt.c
@@ -0,0 +1,3391 @@
+/*
+ * tclClockFmt.c --
+ *
+ *	Contains the date format (and scan) routines. This code is back-ported
+ *	from the time and date facilities of tclSE engine, by Serg G. Brester.
+ *
+ * Copyright (c) 2015 by Sergey G. Brester aka sebres. All rights reserved.
+ *
+ * See the file "license.terms" for information on usage and redistribution of
+ * this file, and for a DISCLAIMER OF ALL WARRANTIES.
+ */
+
+#include "tclInt.h"
+#include "tclStrIdxTree.h"
+#include "tclDate.h"
+
+/*
+ * Miscellaneous forward declarations and functions used within this file
+ */
+
+static void
+ClockFmtObj_DupInternalRep(Tcl_Obj *srcPtr, Tcl_Obj *copyPtr);
+static void
+ClockFmtObj_FreeInternalRep(Tcl_Obj *objPtr);
+static int
+ClockFmtObj_SetFromAny(Tcl_Interp *interp, Tcl_Obj *objPtr);
+static void
+ClockFmtObj_UpdateString(Tcl_Obj *objPtr);
+
+
+TCL_DECLARE_MUTEX(ClockFmtMutex); /* Serializes access to common format list. */
+
+static void ClockFmtScnStorageDelete(ClockFmtScnStorage *fss);
+
+static void ClockFrmScnFinalize(void *clientData);
+
+/*
+ * Clock scan and format facilities.
+ */
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * _str2int -- , _str2wideInt --
+ *
+ *	Fast inline-convertion of string to signed int or wide int by given
+ *	start/end.
+ *
+ *	The given string should contain numbers chars only (because already
+ *	pre-validated within parsing routines)
+ *
+ * Results:
+ *	Returns a standard Tcl result.
+ *	TCL_OK - by successful conversion, TCL_ERROR by (wide) int overflow
+ *
+ *----------------------------------------------------------------------
+ */
+
+/* int overflows may happens here (expected case) */
+#if defined(__GNUC__) || defined(__GNUG__)
+# pragma GCC optimize("no-trapv")
+#endif
+
+static inline int
+_str2int(
+    int	       *out,
+    const char *p,
+    const char *e,
+    int sign)
+{
+    int val = 0, prev = 0;
+    if (sign >= 0) {
+	while (p < e) {
+	    val = val * 10 + (*p++ - '0');
+	    if (val < prev) {
+		return TCL_ERROR;
+	    }
+	    prev = val;
+	}
+    } else {
+	while (p < e) {
+	    val = val * 10 - (*p++ - '0');
+	    if (val > prev) {
+		return TCL_ERROR;
+	    }
+	    prev = val;
+	}
+    }
+    *out = val;
+    return TCL_OK;
+}
+
+static inline int
+_str2wideInt(
+    Tcl_WideInt *out,
+    const char	*p,
+    const char	*e,
+    int sign)
+{
+    Tcl_WideInt val = 0, prev = 0;
+    if (sign >= 0) {
+	while (p < e) {
+	    val = val * 10 + (*p++ - '0');
+	    if (val < prev) {
+		return TCL_ERROR;
+	    }
+	    prev = val;
+	}
+    } else {
+	while (p < e) {
+	    val = val * 10 - (*p++ - '0');
+	    if (val > prev) {
+		return TCL_ERROR;
+	    }
+	    prev = val;
+	}
+    }
+    *out = val;
+    return TCL_OK;
+}
+
+#if defined(__GNUC__) || defined(__GNUG__)
+# pragma GCC reset_options
+#endif
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * _itoaw -- , _witoaw --
+ *
+ *	Fast inline-convertion of signed int or wide int to string, using
+ *	given padding with specified padchar and width (or without padding).
+ *
+ *	This is a very fast replacement for sprintf("%02d").
+ *
+ * Results:
+ *	Returns position in buffer after end of conversion result.
+ *
+ *----------------------------------------------------------------------
+ */
+
+static inline char *
+_itoaw(
+    char *buf,
+    int val,
+    char  padchar,
+    unsigned short int width)
+{
+    char *p;
+    static int wrange[] = {1, 10, 100, 1000, 10000, 100000, 1000000, 10000000, 100000000, 1000000000};
+
+    /* positive integer */
+
+    if (val >= 0)
+    {
+	/* check resp. recalculate width */
+	while (width <= 9 && val >= wrange[width]) {
+	    width++;
+	}
+	/* number to string backwards */
+	p = buf + width;
+	*p-- = '\0';
+	do {
+	    char c = (val % 10); val /= 10;
+	    *p-- = '0' + c;
+	} while (val > 0);
+	/* fulling with pad-char */
+	while (p >= buf) {
+	    *p-- = padchar;
+	}
+
+	return buf + width;
+    }
+    /* negative integer */
+
+    if (!width) width++;
+    /* check resp. recalculate width (regarding sign) */
+    width--;
+    while (width <= 9 && val <= -wrange[width]) {
+	width++;
+    }
+    width++;
+    /* number to string backwards */
+    p = buf + width;
+    *p-- = '\0';
+    /* differentiate platforms with -1 % 10 == 1 and -1 % 10 == -1 */
+    if (-1 % 10 == -1) {
+	do {
+	    char c = (val % 10); val /= 10;
+	    *p-- = '0' - c;
+	} while (val < 0);
+    } else {
+	do {
+	    char c = (val % 10); val /= 10;
+	    *p-- = '0' + c;
+	} while (val < 0);
+    }
+    /* sign by 0 padding */
+    if (padchar != '0') { *p-- = '-'; }
+    /* fulling with pad-char */
+    while (p >= buf + 1) {
+	*p-- = padchar;
+    }
+    /* sign by non 0 padding */
+    if (padchar == '0') { *p = '-'; }
+
+    return buf + width;
+}
+char *
+TclItoAw(
+    char *buf,
+    int val,
+    char  padchar,
+    unsigned short int width)
+{
+    return _itoaw(buf, val, padchar, width);
+}
+
+static inline char *
+_witoaw(
+    char *buf,
+    Tcl_WideInt val,
+    char  padchar,
+    unsigned short int width)
+{
+    char *p;
+    static int wrange[] = {1, 10, 100, 1000, 10000, 100000, 1000000, 10000000, 100000000, 1000000000};
+
+    /* positive integer */
+
+    if (val >= 0)
+    {
+	/* check resp. recalculate width */
+	if (val >= 10000000000LL) {
+	    Tcl_WideInt val2;
+	    val2 = val / 10000000000LL;
+	    while (width <= 9 && val2 >= wrange[width]) {
+		width++;
+	    }
+	    width += 10;
+	} else {
+	    while (width <= 9 && val >= wrange[width]) {
+		width++;
+	    }
+	}
+	/* number to string backwards */
+	p = buf + width;
+	*p-- = '\0';
+	do {
+	    char c = (val % 10); val /= 10;
+	    *p-- = '0' + c;
+	} while (val > 0);
+	/* fulling with pad-char */
+	while (p >= buf) {
+	    *p-- = padchar;
+	}
+
+	return buf + width;
+    }
+
+    /* negative integer */
+
+    if (!width) width++;
+    /* check resp. recalculate width (regarding sign) */
+    width--;
+    if (val <= -10000000000LL) {
+	Tcl_WideInt val2;
+	val2 = val / 10000000000LL;
+	while (width <= 9 && val2 <= -wrange[width]) {
+	    width++;
+	}
+	width += 10;
+    } else {
+	while (width <= 9 && val <= -wrange[width]) {
+	    width++;
+	}
+    }
+    width++;
+    /* number to string backwards */
+    p = buf + width;
+    *p-- = '\0';
+    /* differentiate platforms with -1 % 10 == 1 and -1 % 10 == -1 */
+    if (-1 % 10 == -1) {
+	do {
+	    char c = (val % 10); val /= 10;
+	    *p-- = '0' - c;
+	} while (val < 0);
+    } else {
+	do {
+	    char c = (val % 10); val /= 10;
+	    *p-- = '0' + c;
+	} while (val < 0);
+    }
+    /* sign by 0 padding */
+    if (padchar != '0') { *p-- = '-'; }
+    /* fulling with pad-char */
+    while (p >= buf + 1) {
+	*p-- = padchar;
+    }
+    /* sign by non 0 padding */
+    if (padchar == '0') { *p = '-'; }
+
+    return buf + width;
+}
+
+/*
+ * Global GC as LIFO for released scan/format object storages.
+ *
+ * Used to holds last released CLOCK_FMT_SCN_STORAGE_GC_SIZE formats
+ * (after last reference from Tcl-object will be removed). This is helpful
+ * to avoid continuous (re)creation and compiling by some dynamically resp.
+ * variable format objects, that could be often reused.
+ *
+ * As long as format storage is used resp. belongs to GC, it takes place in
+ * FmtScnHashTable also.
+ */
+
+#if CLOCK_FMT_SCN_STORAGE_GC_SIZE > 0
+
+static struct {
+    ClockFmtScnStorage	  *stackPtr;
+    ClockFmtScnStorage	  *stackBound;
+    unsigned int	   count;
+} ClockFmtScnStorage_GC = {NULL, NULL, 0};
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * ClockFmtScnStorageGC_In --
+ *
+ *	Adds an format storage object to GC.
+ *
+ *	If current GC is full (size larger as CLOCK_FMT_SCN_STORAGE_GC_SIZE)
+ *	this removes last unused storage at begin of GC stack (LIFO).
+ *
+ *	Assumes caller holds the ClockFmtMutex.
+ *
+ * Results:
+ *	None.
+ *
+ *----------------------------------------------------------------------
+ */
+
+static inline void
+ClockFmtScnStorageGC_In(ClockFmtScnStorage *entry)
+{
+    /* add new entry */
+    TclSpliceIn(entry, ClockFmtScnStorage_GC.stackPtr);
+    if (ClockFmtScnStorage_GC.stackBound == NULL) {
+	ClockFmtScnStorage_GC.stackBound = entry;
+    }
+    ClockFmtScnStorage_GC.count++;
+
+    /* if GC ist full */
+    if (ClockFmtScnStorage_GC.count > CLOCK_FMT_SCN_STORAGE_GC_SIZE) {
+
+	/* GC stack is LIFO: delete first inserted entry */
+	ClockFmtScnStorage *delEnt = ClockFmtScnStorage_GC.stackBound;
+	ClockFmtScnStorage_GC.stackBound = delEnt->prevPtr;
+	TclSpliceOut(delEnt, ClockFmtScnStorage_GC.stackPtr);
+	ClockFmtScnStorage_GC.count--;
+	delEnt->prevPtr = delEnt->nextPtr = NULL;
+	/* remove it now */
+	ClockFmtScnStorageDelete(delEnt);
+    }
+}
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * ClockFmtScnStorage_GC_Out --
+ *
+ *	Restores (for reusing) given format storage object from GC.
+ *
+ *	Assumes caller holds the ClockFmtMutex.
+ *
+ * Results:
+ *	None.
+ *
+ *----------------------------------------------------------------------
+ */
+
+static inline void
+ClockFmtScnStorage_GC_Out(ClockFmtScnStorage *entry)
+{
+    TclSpliceOut(entry, ClockFmtScnStorage_GC.stackPtr);
+    ClockFmtScnStorage_GC.count--;
+    if (ClockFmtScnStorage_GC.stackBound == entry) {
+	ClockFmtScnStorage_GC.stackBound = entry->prevPtr;
+    }
+    entry->prevPtr = entry->nextPtr = NULL;
+}
+
+#endif
+
+
+/*
+ * Global format storage hash table of type ClockFmtScnStorageHashKeyType
+ * (contains list of scan/format object storages, shared across all threads).
+ *
+ * Used for fast searching by format string.
+ */
+static Tcl_HashTable FmtScnHashTable;
+static int	     initialized = 0;
+
+/*
+ * Wrappers between pointers to hash entry and format storage object
+ */
+static inline Tcl_HashEntry *
+HashEntry4FmtScn(ClockFmtScnStorage *fss) {
+    return (Tcl_HashEntry*)(fss + 1);
+};
+static inline ClockFmtScnStorage *
+FmtScn4HashEntry(Tcl_HashEntry *hKeyPtr) {
+    return (ClockFmtScnStorage*)(((char*)hKeyPtr) - sizeof(ClockFmtScnStorage));
+};
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * ClockFmtScnStorageAllocProc --
+ *
+ *	Allocate space for a hash entry containing format storage together
+ *	with the string key.
+ *
+ * Results:
+ *	The return value is a pointer to the created entry.
+ *
+ *----------------------------------------------------------------------
+ */
+
+static Tcl_HashEntry *
+ClockFmtScnStorageAllocProc(
+    TCL_UNUSED(Tcl_HashTable *),	/* Hash table. */
+    void *keyPtr)		/* Key to store in the hash table entry. */
+{
+    ClockFmtScnStorage *fss;
+    const char *string = (const char *) keyPtr;
+    Tcl_HashEntry *hPtr;
+    unsigned int size,
+	allocsize = sizeof(ClockFmtScnStorage) + sizeof(Tcl_HashEntry);
+
+    allocsize += (size = strlen(string) + 1);
+    if (size > sizeof(hPtr->key)) {
+	allocsize -= sizeof(hPtr->key);
+    }
+
+    fss = (ClockFmtScnStorage *)Tcl_Alloc(allocsize);
+
+    /* initialize */
+    memset(fss, 0, sizeof(*fss));
+
+    hPtr = HashEntry4FmtScn(fss);
+    memcpy(&hPtr->key.string, string, size);
+    hPtr->clientData = 0; /* currently unused */
+
+    return hPtr;
+}
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * ClockFmtScnStorageFreeProc --
+ *
+ *	Free format storage object and space of given hash entry.
+ *
+ * Results:
+ *	None.
+ *
+ *----------------------------------------------------------------------
+ */
+
+static void
+ClockFmtScnStorageFreeProc(
+    Tcl_HashEntry *hPtr)
+{
+    ClockFmtScnStorage *fss = FmtScn4HashEntry(hPtr);
+
+    if (fss->scnTok != NULL) {
+	Tcl_Free(fss->scnTok);
+	fss->scnTok = NULL;
+	fss->scnTokC = 0;
+    }
+    if (fss->fmtTok != NULL) {
+	Tcl_Free(fss->fmtTok);
+	fss->fmtTok = NULL;
+	fss->fmtTokC = 0;
+    }
+
+    Tcl_Free(fss);
+}
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * ClockFmtScnStorageDelete --
+ *
+ *	Delete format storage object.
+ *
+ * Results:
+ *	None.
+ *
+ *----------------------------------------------------------------------
+ */
+
+static void
+ClockFmtScnStorageDelete(ClockFmtScnStorage *fss) {
+    Tcl_HashEntry   *hPtr = HashEntry4FmtScn(fss);
+    /*
+     * This will delete a hash entry and call "Tcl_Free" for storage self, if
+     * some additionally handling required, freeEntryProc can be used instead
+     */
+    Tcl_DeleteHashEntry(hPtr);
+}
+
+
+/*
+ * Derivation of tclStringHashKeyType with another allocEntryProc
+ */
+
+static Tcl_HashKeyType ClockFmtScnStorageHashKeyType;
+
+
+/*
+ * Type definition of clock-format tcl object type.
+ */
+
+static const Tcl_ObjType ClockFmtObjType = {
+    "clock-format",	       /* name */
+    ClockFmtObj_FreeInternalRep, /* freeIntRepProc */
+    ClockFmtObj_DupInternalRep,	 /* dupIntRepProc */
+    ClockFmtObj_UpdateString,	 /* updateStringProc */
+    ClockFmtObj_SetFromAny,	 /* setFromAnyProc */
+    TCL_OBJTYPE_V0
+};
+
+#define ObjClockFmtScn(objPtr) \
+    (*((ClockFmtScnStorage **)&(objPtr)->internalRep.twoPtrValue.ptr1))
+
+#define ObjLocFmtKey(objPtr) \
+    (*((Tcl_Obj **)&(objPtr)->internalRep.twoPtrValue.ptr2))
+
+static void
+ClockFmtObj_DupInternalRep(
+    Tcl_Obj *srcPtr,
+    Tcl_Obj *copyPtr)
+{
+    ClockFmtScnStorage *fss = ObjClockFmtScn(srcPtr);
+
+    if (fss != NULL) {
+	Tcl_MutexLock(&ClockFmtMutex);
+	fss->objRefCount++;
+	Tcl_MutexUnlock(&ClockFmtMutex);
+    }
+
+    ObjClockFmtScn(copyPtr) = fss;
+    /* regards special case - format not localizable */
+    if (ObjLocFmtKey(srcPtr) != srcPtr) {
+	Tcl_InitObjRef(ObjLocFmtKey(copyPtr), ObjLocFmtKey(srcPtr));
+    } else {
+	ObjLocFmtKey(copyPtr) = copyPtr;
+    }
+    copyPtr->typePtr = &ClockFmtObjType;
+
+
+    /* if no format representation, dup string representation */
+    if (fss == NULL) {
+	copyPtr->bytes = (char *)Tcl_Alloc(srcPtr->length + 1);
+	memcpy(copyPtr->bytes, srcPtr->bytes, srcPtr->length + 1);
+	copyPtr->length = srcPtr->length;
+    }
+}
+
+static void
+ClockFmtObj_FreeInternalRep(
+    Tcl_Obj *objPtr)
+{
+    ClockFmtScnStorage *fss = ObjClockFmtScn(objPtr);
+    if (fss != NULL) {
+	Tcl_MutexLock(&ClockFmtMutex);
+	/* decrement object reference count of format/scan storage */
+	if (--fss->objRefCount <= 0) {
+	    #if CLOCK_FMT_SCN_STORAGE_GC_SIZE > 0
+	      /* don't remove it right now (may be reusable), just add to GC */
+	      ClockFmtScnStorageGC_In(fss);
+	    #else
+	      /* remove storage (format representation) */
+	      ClockFmtScnStorageDelete(fss);
+	    #endif
+	}
+	Tcl_MutexUnlock(&ClockFmtMutex);
+    }
+    ObjClockFmtScn(objPtr) = NULL;
+    if (ObjLocFmtKey(objPtr) != objPtr) {
+	Tcl_UnsetObjRef(ObjLocFmtKey(objPtr));
+    } else {
+	ObjLocFmtKey(objPtr) = NULL;
+    }
+    objPtr->typePtr = NULL;
+};
+
+static int
+ClockFmtObj_SetFromAny(
+    TCL_UNUSED(Tcl_Interp *),
+    Tcl_Obj    *objPtr)
+{
+    /* validate string representation before free old internal representation */
+    (void)TclGetString(objPtr);
+
+    /* free old internal representation */
+    if (objPtr->typePtr && objPtr->typePtr->freeIntRepProc)
+	objPtr->typePtr->freeIntRepProc(objPtr);
+
+    /* initial state of format object */
+    ObjClockFmtScn(objPtr) = NULL;
+    ObjLocFmtKey(objPtr) = NULL;
+    objPtr->typePtr = &ClockFmtObjType;
+
+    return TCL_OK;
+};
+
+static void
+ClockFmtObj_UpdateString(
+    Tcl_Obj  *objPtr)
+{
+    const char *name = "UNKNOWN";
+    size_t len;
+    ClockFmtScnStorage *fss = ObjClockFmtScn(objPtr);
+
+    if (fss != NULL) {
+	Tcl_HashEntry *hPtr = HashEntry4FmtScn(fss);
+	name = hPtr->key.string;
+    }
+    len = strlen(name);
+    objPtr->length = len++,
+    objPtr->bytes = (char *)Tcl_Alloc(len);
+    if (objPtr->bytes) {
+	memcpy(objPtr->bytes, name, len);
+    }
+}
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * ClockFrmObjGetLocFmtKey --
+ *
+ *	Retrieves format key object used to search localized format.
+ *
+ *	This is normally stored in second pointer of internal representation.
+ *	If format object is not localizable, it is equal the given format
+ *	pointer (special case to fast fallback by not-localizable formats).
+ *
+ * Results:
+ *	Returns tcl object with key or format object if not localizable.
+ *
+ * Side effects:
+ * 	Converts given format object to ClockFmtObjType on demand for caching
+ *	the key inside its internal representation.
+ *
+ *----------------------------------------------------------------------
+ */
+
+Tcl_Obj*
+ClockFrmObjGetLocFmtKey(
+    Tcl_Interp *interp,
+    Tcl_Obj    *objPtr)
+{
+    Tcl_Obj *keyObj;
+
+    if (objPtr->typePtr != &ClockFmtObjType) {
+	if (ClockFmtObj_SetFromAny(interp, objPtr) != TCL_OK) {
+	    return NULL;
+	}
+    }
+
+    keyObj = ObjLocFmtKey(objPtr);
+    if (keyObj) {
+	return keyObj;
+    }
+
+    keyObj = Tcl_ObjPrintf("FMT_%s", TclGetString(objPtr));
+    Tcl_InitObjRef(ObjLocFmtKey(objPtr), keyObj);
+
+    return keyObj;
+}
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * FindOrCreateFmtScnStorage --
+ *
+ *	Retrieves format storage for given string format.
+ *
+ *	This will find the given format in the global storage hash table
+ *	or create a format storage object on demaind and save the
+ *	reference in the first pointer of internal representation of given
+ *	object.
+ *
+ * Results:
+ *	Returns scan/format storage pointer to ClockFmtScnStorage.
+ *
+ * Side effects:
+ * 	Converts given format object to ClockFmtObjType on demand for caching
+ *	the format storage reference inside its internal representation.
+ *	Increments objRefCount of the ClockFmtScnStorage reference.
+ *
+ *----------------------------------------------------------------------
+ */
+
+static ClockFmtScnStorage *
+FindOrCreateFmtScnStorage(
+    Tcl_Interp *interp,
+    Tcl_Obj    *objPtr)
+{
+    const char *strFmt = TclGetString(objPtr);
+    ClockFmtScnStorage *fss = NULL;
+    int isNew;
+    Tcl_HashEntry *hPtr;
+
+    Tcl_MutexLock(&ClockFmtMutex);
+
+    /* if not yet initialized */
+    if (!initialized) {
+	/* initialize type */
+	memcpy(&ClockFmtScnStorageHashKeyType, &tclStringHashKeyType, sizeof(tclStringHashKeyType));
+	ClockFmtScnStorageHashKeyType.allocEntryProc = ClockFmtScnStorageAllocProc;
+	ClockFmtScnStorageHashKeyType.freeEntryProc = ClockFmtScnStorageFreeProc;
+
+	/* initialize hash table */
+	Tcl_InitCustomHashTable(&FmtScnHashTable, TCL_CUSTOM_TYPE_KEYS,
+	    &ClockFmtScnStorageHashKeyType);
+
+	initialized = 1;
+	Tcl_CreateExitHandler(ClockFrmScnFinalize, NULL);
+    }
+
+    /* get or create entry (and alocate storage) */
+    hPtr = Tcl_CreateHashEntry(&FmtScnHashTable, strFmt, &isNew);
+    if (hPtr != NULL) {
+
+	fss = FmtScn4HashEntry(hPtr);
+
+	#if CLOCK_FMT_SCN_STORAGE_GC_SIZE > 0
+	  /* unlink if it is currently in GC */
+	  if (isNew == 0 && fss->objRefCount == 0) {
+	      ClockFmtScnStorage_GC_Out(fss);
+	  }
+	#endif
+
+	/* new reference, so increment in lock right now */
+	fss->objRefCount++;
+
+	ObjClockFmtScn(objPtr) = fss;
+    }
+
+    Tcl_MutexUnlock(&ClockFmtMutex);
+
+    if (fss == NULL && interp != NULL) {
+	Tcl_AppendResult(interp, "retrieve clock format failed \"",
+	    strFmt ? strFmt : "", "\"", NULL);
+	Tcl_SetErrorCode(interp, "TCL", "EINVAL", (char *)NULL);
+    }
+
+    return fss;
+}
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * Tcl_GetClockFrmScnFromObj --
+ *
+ *	Returns a clock format/scan representation of (*objPtr), if possible.
+ *	If something goes wrong, NULL is returned, and if interp is non-NULL,
+ *	an error message is written there.
+ *
+ * Results:
+ *	Valid representation of type ClockFmtScnStorage.
+ *
+ * Side effects:
+ *	Caches the ClockFmtScnStorage reference as the internal rep of (*objPtr)
+ *	and in global hash table, shared across all threads.
+ *
+ *----------------------------------------------------------------------
+ */
+
+ClockFmtScnStorage *
+Tcl_GetClockFrmScnFromObj(
+    Tcl_Interp *interp,
+    Tcl_Obj *objPtr)
+{
+    ClockFmtScnStorage *fss;
+
+    if (objPtr->typePtr != &ClockFmtObjType) {
+	if (ClockFmtObj_SetFromAny(interp, objPtr) != TCL_OK) {
+	    return NULL;
+	}
+    }
+
+    fss = ObjClockFmtScn(objPtr);
+
+    if (fss == NULL) {
+	fss = FindOrCreateFmtScnStorage(interp, objPtr);
+    }
+
+    return fss;
+}
+/*
+ *----------------------------------------------------------------------
+ *
+ * ClockLocalizeFormat --
+ *
+ *	Wrap the format object in options to the localized format,
+ *	corresponding given locale.
+ *
+ *	This searches localized format in locale catalog, and if not yet
+ *	exists, it executes ::tcl::clock::LocalizeFormat in given interpreter
+ *	and caches its result in the locale catalog.
+ *
+ * Results:
+ *	Localized format object.
+ *
+ * Side effects:
+ *	Caches the localized format inside locale catalog.
+ *
+ *----------------------------------------------------------------------
+ */
+
+Tcl_Obj *
+ClockLocalizeFormat(
+    ClockFmtScnCmdArgs *opts)
+{
+    ClockClientData *dataPtr = (ClockClientData *)opts->clientData;
+    Tcl_Obj *valObj = NULL, *keyObj;
+
+    keyObj = ClockFrmObjGetLocFmtKey(opts->interp, opts->formatObj);
+
+    /* special case - format object is not localizable */
+    if (keyObj == opts->formatObj) {
+	return opts->formatObj;
+    }
+
+    /* prevents loss of key object if the format object (where key stored)
+     * becomes changed (loses its internal representation during evals) */
+    Tcl_IncrRefCount(keyObj);
+
+    if (opts->mcDictObj == NULL) {
+	ClockMCDict(opts);
+	if (opts->mcDictObj == NULL)
+	    goto done;
+    }
+
+    /* try to find in cache within locale mc-catalog */
+    if (Tcl_DictObjGet(NULL, opts->mcDictObj,
+	    keyObj, &valObj) != TCL_OK) {
+	goto done;
+    }
+
+    /* call LocalizeFormat locale format fmtkey */
+    if (valObj == NULL) {
+	Tcl_Obj *callargs[4];
+	callargs[0] = dataPtr->literals[LIT_LOCALIZE_FORMAT];
+	callargs[1] = opts->localeObj;
+	callargs[2] = opts->formatObj;
+	callargs[3] = opts->mcDictObj;
+	if (Tcl_EvalObjv(opts->interp, 4, callargs, 0) == TCL_OK
+	) {
+	    valObj = Tcl_GetObjResult(opts->interp);
+	}
+
+	/* ensure mcDictObj remains unshared */
+	if (opts->mcDictObj->refCount > 1) {
+	    /* smart reference (shared dict as object with no ref-counter) */
+	    opts->mcDictObj = TclDictObjSmartRef(opts->interp,
+		opts->mcDictObj);
+	}
+	if (!valObj) {
+	    goto done;
+	}
+	/* cache it inside mc-dictionary (this incr. ref count of keyObj/valObj) */
+	if (Tcl_DictObjPut(opts->interp, opts->mcDictObj,
+		keyObj, valObj) != TCL_OK
+	) {
+	    valObj = NULL;
+	    goto done;
+	}
+
+	Tcl_ResetResult(opts->interp);
+
+	/* check special case - format object is not localizable */
+	if (valObj == opts->formatObj) {
+	    /* mark it as unlocalizable, by setting self as key (without refcount incr) */
+	    if (valObj->typePtr == &ClockFmtObjType) {
+		Tcl_UnsetObjRef(ObjLocFmtKey(valObj));
+		ObjLocFmtKey(valObj) = valObj;
+	    }
+	}
+    }
+
+done:
+
+    Tcl_UnsetObjRef(keyObj);
+    return (opts->formatObj = valObj);
+}
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * FindTokenBegin --
+ *
+ *	Find begin of given scan token in string, corresponding token type.
+ *
+ * Results:
+ *	Position of token inside string if found. Otherwise - end of string.
+ *
+ * Side effects:
+ *	None.
+ *
+ *----------------------------------------------------------------------
+ */
+
+static const char *
+FindTokenBegin(
+    const char *p,
+    const char *end,
+    ClockScanToken *tok)
+{
+    char c;
+    if (p < end) {
+	/* next token a known token type */
+	switch (tok->map->type) {
+	case CTOKT_INT:
+	case CTOKT_WIDE:
+	    /* should match at least one digit */
+	    while (!isdigit(UCHAR(*p)) && (p = Tcl_UtfNext(p)) < end) {};
+	    return p;
+	break;
+	case CTOKT_WORD:
+	    c = *(tok->tokWord.start);
+	    /* should match at least to the first char of this word */
+	    while (*p != c && (p = Tcl_UtfNext(p)) < end) {};
+	    return p;
+	break;
+	case CTOKT_SPACE:
+	    while (!isspace(UCHAR(*p)) && (p = Tcl_UtfNext(p)) < end) {};
+	    return p;
+	break;
+	case CTOKT_CHAR:
+	    c = *((char *)tok->map->data);
+	    while (*p != c && (p = Tcl_UtfNext(p)) < end) {};
+	    return p;
+	break;
+	}
+    }
+    return p;
+}
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * DetermineGreedySearchLen --
+ *
+ *	Determine min/max lengths as exact as possible (speed, greedy match).
+ *
+ * Results:
+ *	None. Lengths are stored in *minLenPtr, *maxLenPtr.
+ *
+ * Side effects:
+ *	None.
+ *
+ *----------------------------------------------------------------------
+ */
+
+static void
+DetermineGreedySearchLen(
+    DateInfo *info, ClockScanToken *tok,
+    int *minLenPtr, int *maxLenPtr)
+{
+    int minLen = tok->map->minSize;
+    int maxLen;
+    const char *p = yyInput + minLen,
+			*end = info->dateEnd;
+
+    /* if still tokens available, try to correct minimum length */
+    if ((tok+1)->map) {
+	end -= tok->endDistance + yySpaceCount;
+	/* find position of next known token */
+	p = FindTokenBegin(p, end, tok+1);
+	if (p < end) {
+	    minLen = p - yyInput;
+	}
+    }
+
+    /* max length to the end regarding distance to end (min-width of following tokens) */
+    maxLen = end - yyInput;
+    /* several amendments */
+    if (maxLen > tok->map->maxSize) {
+	maxLen = tok->map->maxSize;
+    };
+    if (minLen < tok->map->minSize) {
+	minLen = tok->map->minSize;
+    }
+    if (minLen > maxLen) {
+	maxLen = minLen;
+    }
+    if (maxLen > info->dateEnd - yyInput) {
+	maxLen = info->dateEnd - yyInput;
+    }
+
+    /* check digits rigth now */
+    if (tok->map->type == CTOKT_INT || tok->map->type == CTOKT_WIDE) {
+	p = yyInput;
+	end = p + maxLen;
+	if (end > info->dateEnd) { end = info->dateEnd; };
+	while (isdigit(UCHAR(*p)) && p < end) { p++; };
+	maxLen = p - yyInput;
+    }
+
+    /* try to get max length more precise for greedy match,
+     * check the next ahead token available there */
+    if (minLen < maxLen && tok->lookAhTok) {
+	ClockScanToken *laTok = tok + tok->lookAhTok + 1;
+	p = yyInput + maxLen;
+	/* regards all possible spaces here (because they are optional) */
+	end = p + tok->lookAhMax + yySpaceCount + 1;
+	if (end > info->dateEnd) {
+	    end = info->dateEnd;
+	}
+	p += tok->lookAhMin;
+	if (laTok->map && p < end) {
+	    const char *f;
+	    /* try to find laTok between [lookAhMin, lookAhMax] */
+	    while (minLen < maxLen) {
+		f = FindTokenBegin(p, end, laTok);
+		/* if found (not below lookAhMax) */
+		if (f < end) {
+		    break;
+		}
+		/* try again with fewer length */
+		maxLen--;
+		p--;
+		end--;
+	    }
+	} else if (p > end) {
+	    maxLen -= (p - end);
+	    if (maxLen < minLen) {
+		maxLen = minLen;
+	    }
+	}
+    }
+
+    *minLenPtr = minLen;
+    *maxLenPtr = maxLen;
+}
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * ObjListSearch --
+ *
+ *	Find largest part of the input string from start regarding min and
+ *	max lengths in the given list (utf-8, case sensitive).
+ *
+ * Results:
+ *	TCL_OK - match found, TCL_RETURN - not matched, TCL_ERROR in error case.
+ *
+ * Side effects:
+ *	Input points to end of the found token in string.
+ *
+ *----------------------------------------------------------------------
+ */
+
+static inline int
+ObjListSearch(
+    DateInfo *info, int *val,
+    Tcl_Obj **lstv, Tcl_Size lstc,
+    int minLen, int maxLen)
+{
+    Tcl_Size i, l, lf = -1;
+    const char *s, *f, *sf;
+    /* search in list */
+    for (i = 0; i < lstc; i++) {
+	s = TclGetStringFromObj(lstv[i], &l);
+
+	if ( l >= minLen
+	  && (f = TclUtfFindEqualNC(yyInput, yyInput + maxLen, s, s + l, &sf)) > yyInput
+	) {
+	    l = f - yyInput;
+	    if (l < minLen) {
+		continue;
+	    }
+	    /* found, try to find longest value (greedy search) */
+	    if (l < maxLen && minLen != maxLen) {
+		lf = i;
+		minLen = l + 1;
+		continue;
+	    }
+	    /* max possible - end of search */
+	    *val = i;
+	    yyInput += l;
+	    break;
+	}
+    }
+
+    /* if found */
+    if (i < lstc) {
+	return TCL_OK;
+    }
+    if (lf >= 0) {
+	*val = lf;
+	yyInput += minLen - 1;
+	return TCL_OK;
+    }
+    return TCL_RETURN;
+}
+#if 0
+/* currently unused */
+
+static int
+LocaleListSearch(ClockFmtScnCmdArgs *opts,
+    DateInfo *info, int mcKey, int *val,
+    int minLen, int maxLen)
+{
+    Tcl_Obj **lstv;
+    Tcl_Size lstc;
+    Tcl_Obj *valObj;
+
+    /* get msgcat value */
+    valObj = ClockMCGet(opts, mcKey);
+    if (valObj == NULL) {
+	return TCL_ERROR;
+    }
+
+    /* is a list */
+    if (TclListObjGetElements(opts->interp, valObj, &lstc, &lstv) != TCL_OK) {
+	return TCL_ERROR;
+    }
+
+    /* search in list */
+    return ObjListSearch(info, val, lstv, lstc,
+	minLen, maxLen);
+}
+#endif
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * ClockMCGetListIdxTree --
+ *
+ *	Retrieves localized string indexed tree in the locale catalog for
+ *	given literal index mcKey (and builds it on demand).
+ *
+ *	Searches localized index in locale catalog, and if not yet exists,
+ *	creates string indexed tree and stores it in the locale catalog.
+ *
+ * Results:
+ *	Localized string index tree.
+ *
+ * Side effects:
+ *	Caches the localized string index tree inside locale catalog.
+ *
+ *----------------------------------------------------------------------
+ */
+
+static TclStrIdxTree *
+ClockMCGetListIdxTree(
+    ClockFmtScnCmdArgs *opts,
+    int	 mcKey)
+{
+    TclStrIdxTree * idxTree;
+    Tcl_Obj *objPtr = ClockMCGetIdx(opts, mcKey);
+    if ( objPtr != NULL
+      && (idxTree = TclStrIdxTreeGetFromObj(objPtr)) != NULL
+    ) {
+	return idxTree;
+
+    } else {
+	/* build new index */
+
+	Tcl_Obj **lstv;
+	Tcl_Size lstc;
+	Tcl_Obj *valObj;
+
+	objPtr = TclStrIdxTreeNewObj();
+	if ((idxTree = TclStrIdxTreeGetFromObj(objPtr)) == NULL) {
+	    goto done; /* unexpected, but ...*/
+	}
+
+	valObj = ClockMCGet(opts, mcKey);
+	if (valObj == NULL) {
+	    goto done;
+	}
+
+	if (TclListObjGetElements(opts->interp, valObj,
+		&lstc, &lstv) != TCL_OK) {
+	    goto done;
+	};
+
+	if (TclStrIdxTreeBuildFromList(idxTree, lstc, lstv, NULL) != TCL_OK) {
+	    goto done;
+	}
+
+	ClockMCSetIdx(opts, mcKey, objPtr);
+	objPtr = NULL;
+    };
+
+done:
+    if (objPtr) {
+	Tcl_DecrRefCount(objPtr);
+	idxTree = NULL;
+    }
+
+    return idxTree;
+}
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * ClockMCGetMultiListIdxTree --
+ *
+ *	Retrieves localized string indexed tree in the locale catalog for
+ *	multiple lists by literal indices mcKeys (and builds it on demand).
+ *
+ *	Searches localized index in locale catalog for mcKey, and if not
+ *	yet exists, creates string indexed tree and stores it in the
+ *	locale catalog.
+ *
+ * Results:
+ *	Localized string index tree.
+ *
+ * Side effects:
+ *	Caches the localized string index tree inside locale catalog.
+ *
+ *----------------------------------------------------------------------
+ */
+
+static TclStrIdxTree *
+ClockMCGetMultiListIdxTree(
+    ClockFmtScnCmdArgs *opts,
+    int	 mcKey,
+    int *mcKeys)
+{
+    TclStrIdxTree * idxTree;
+    Tcl_Obj *objPtr = ClockMCGetIdx(opts, mcKey);
+    if ( objPtr != NULL
+      && (idxTree = TclStrIdxTreeGetFromObj(objPtr)) != NULL
+    ) {
+	return idxTree;
+
+    } else {
+	/* build new index */
+
+	Tcl_Obj **lstv;
+	Tcl_Size	  lstc;
+	Tcl_Obj *valObj;
+
+	objPtr = TclStrIdxTreeNewObj();
+	if ((idxTree = TclStrIdxTreeGetFromObj(objPtr)) == NULL) {
+	    goto done; /* unexpected, but ...*/
+	}
+
+	while (*mcKeys) {
+
+	    valObj = ClockMCGet(opts, *mcKeys);
+	    if (valObj == NULL) {
+		goto done;
+	    }
+
+	    if (TclListObjGetElements(opts->interp, valObj,
+		    &lstc, &lstv) != TCL_OK) {
+		goto done;
+	    };
+
+	    if (TclStrIdxTreeBuildFromList(idxTree, lstc, lstv, NULL) != TCL_OK) {
+		goto done;
+	    }
+	    mcKeys++;
+	}
+
+	ClockMCSetIdx(opts, mcKey, objPtr);
+	objPtr = NULL;
+    };
+
+done:
+    if (objPtr) {
+	Tcl_DecrRefCount(objPtr);
+	idxTree = NULL;
+    }
+
+    return idxTree;
+}
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * ClockStrIdxTreeSearch --
+ *
+ *	Find largest part of the input string from start regarding lengths
+ *	in the given localized string indexed tree (utf-8, case sensitive).
+ *
+ * Results:
+ *	TCL_OK - match found and the index stored in *val,
+ *	TCL_RETURN - not matched or ambigous,
+ * 	TCL_ERROR - in error case.
+ *
+ * Side effects:
+ *	Input points to end of the found token in string.
+ *
+ *----------------------------------------------------------------------
+ */
+
+static inline int
+ClockStrIdxTreeSearch(
+    DateInfo *info, TclStrIdxTree *idxTree, int *val,
+    int minLen, int maxLen)
+{
+    const char *f;
+    TclStrIdx  *foundItem;
+    f = TclStrIdxTreeSearch(NULL, &foundItem, idxTree,
+	    yyInput, yyInput + maxLen);
+
+    if (f <= yyInput || (f - yyInput) < minLen) {
+	/* not found */
+	return TCL_RETURN;
+    }
+    if (!foundItem->value) {
+	/* ambigous */
+	return TCL_RETURN;
+    }
+
+    *val = PTR2INT(foundItem->value);
+
+    /* shift input pointer */
+    yyInput = f;
+
+    return TCL_OK;
+}
+#if 0
+/* currently unused */
+
+static int
+StaticListSearch(ClockFmtScnCmdArgs *opts,
+    DateInfo *info, const char **lst, int *val)
+{
+    size_t len;
+    const char **s = lst;
+    while (*s != NULL) {
+	len = strlen(*s);
+	if ( len <= info->dateEnd - yyInput
+	  && strncasecmp(yyInput, *s, len) == 0
+	) {
+	    *val = (s - lst);
+	    yyInput += len;
+	    break;
+	}
+	s++;
+    }
+    if (*s != NULL) {
+	return TCL_OK;
+    }
+    return TCL_RETURN;
+}
+#endif
+
+static inline const char *
+FindWordEnd(
+    ClockScanToken *tok,
+    const char * p, const char * end)
+{
+    const char *x = tok->tokWord.start;
+    const char *pfnd = p;
+    if (x == tok->tokWord.end - 1) { /* fast phase-out for single char word */
+	if (*p == *x) {
+	    return ++p;
+	}
+    }
+    /* multi-char word */
+    x = TclUtfFindEqualNC(x, tok->tokWord.end, p, end, &pfnd);
+    if (x < tok->tokWord.end) {
+	/* no match -> error */
+	return NULL;
+    }
+    return pfnd;
+}
+
+static int
+ClockScnToken_Month_Proc(ClockFmtScnCmdArgs *opts,
+    DateInfo *info, ClockScanToken *tok)
+{
+#if 0
+/* currently unused, test purposes only */
+    static const char * months[] = {
+	/* full */
+	"January", "February", "March",
+	"April",   "May",      "June",
+	"July",	   "August",   "September",
+	"October", "November", "December",
+	/* abbr */
+	"Jan", "Feb", "Mar", "Apr", "May", "Jun",
+	"Jul", "Aug", "Sep", "Oct", "Nov", "Dec",
+	NULL
+    };
+    int val;
+    if (StaticListSearch(opts, info, months, &val) != TCL_OK) {
+	return TCL_RETURN;
+    }
+    yyMonth = (val % 12) + 1;
+    return TCL_OK;
+#endif
+
+    static int monthsKeys[] = {MCLIT_MONTHS_FULL, MCLIT_MONTHS_ABBREV, 0};
+
+    int ret, val;
+    int minLen, maxLen;
+    TclStrIdxTree *idxTree;
+
+    DetermineGreedySearchLen(info, tok, &minLen, &maxLen);
+
+    /* get or create tree in msgcat dict */
+
+    idxTree = ClockMCGetMultiListIdxTree(opts, MCLIT_MONTHS_COMB, monthsKeys);
+    if (idxTree == NULL) {
+	return TCL_ERROR;
+    }
+
+    ret = ClockStrIdxTreeSearch(info, idxTree, &val, minLen, maxLen);
+    if (ret != TCL_OK) {
+	return ret;
+    }
+
+    yyMonth = val;
+    return TCL_OK;
+
+}
+
+static int
+ClockScnToken_DayOfWeek_Proc(ClockFmtScnCmdArgs *opts,
+    DateInfo *info, ClockScanToken *tok)
+{
+    static int dowKeys[] = {MCLIT_DAYS_OF_WEEK_ABBREV, MCLIT_DAYS_OF_WEEK_FULL, 0};
+
+    int ret, val;
+    int minLen, maxLen;
+    char curTok = *tok->tokWord.start;
+    TclStrIdxTree *idxTree;
+
+    DetermineGreedySearchLen(info, tok, &minLen, &maxLen);
+
+    /* %u %w %Ou %Ow */
+    if ( curTok != 'a' && curTok != 'A'
+      && ((minLen <= 1 && maxLen >= 1) || PTR2INT(tok->map->data))
+    ) {
+
+	val = -1;
+
+	if (PTR2INT(tok->map->data) == 0) {
+	    if (*yyInput >= '0' && *yyInput <= '9') {
+		val = *yyInput - '0';
+	    }
+	} else {
+	    idxTree = ClockMCGetListIdxTree(opts, PTR2INT(tok->map->data) /* mcKey */);
+	    if (idxTree == NULL) {
+		return TCL_ERROR;
+	    }
+
+	    ret = ClockStrIdxTreeSearch(info, idxTree, &val, minLen, maxLen);
+	    if (ret != TCL_OK) {
+		return ret;
+	    }
+	    --val;
+	}
+
+	if (val != -1) {
+	    if (val == 0) {
+		val = 7;
+	    }
+	    if (val > 7) {
+		Tcl_SetObjResult(opts->interp, Tcl_NewStringObj("day of week is greater than 7", -1));
+		Tcl_SetErrorCode(opts->interp, "CLOCK", "badDayOfWeek", (char *)NULL);
+		return TCL_ERROR;
+	    }
+	    info->date.dayOfWeek = val;
+	    yyInput++;
+	    return TCL_OK;
+	}
+
+
+	return TCL_RETURN;
+    }
+
+    /* %a %A */
+    idxTree = ClockMCGetMultiListIdxTree(opts, MCLIT_DAYS_OF_WEEK_COMB, dowKeys);
+    if (idxTree == NULL) {
+	return TCL_ERROR;
+    }
+
+    ret = ClockStrIdxTreeSearch(info, idxTree, &val, minLen, maxLen);
+    if (ret != TCL_OK) {
+	return ret;
+    }
+    --val;
+
+    if (val == 0) {
+	val = 7;
+    }
+    info->date.dayOfWeek = val;
+    return TCL_OK;
+
+}
+
+static int
+ClockScnToken_amPmInd_Proc(ClockFmtScnCmdArgs *opts,
+    DateInfo *info, ClockScanToken *tok)
+{
+    int ret, val;
+    int minLen, maxLen;
+    Tcl_Obj *amPmObj[2];
+
+    DetermineGreedySearchLen(info, tok, &minLen, &maxLen);
+
+    amPmObj[0] = ClockMCGet(opts, MCLIT_AM);
+    amPmObj[1] = ClockMCGet(opts, MCLIT_PM);
+
+    if (amPmObj[0] == NULL || amPmObj[1] == NULL) {
+	return TCL_ERROR;
+    }
+
+    ret = ObjListSearch(info, &val, amPmObj, 2,
+	minLen, maxLen);
+    if (ret != TCL_OK) {
+	return ret;
+    }
+
+    if (val == 0) {
+	yyMeridian = MERam;
+    } else {
+	yyMeridian = MERpm;
+    }
+
+    return TCL_OK;
+}
+
+static int
+ClockScnToken_LocaleERA_Proc(ClockFmtScnCmdArgs *opts,
+    DateInfo *info, ClockScanToken *tok)
+{
+    ClockClientData *dataPtr = (ClockClientData *)opts->clientData;
+
+    int ret, val;
+    int minLen, maxLen;
+    Tcl_Obj *eraObj[6];
+
+    DetermineGreedySearchLen(info, tok, &minLen, &maxLen);
+
+    eraObj[0] = ClockMCGet(opts, MCLIT_BCE);
+    eraObj[1] = ClockMCGet(opts, MCLIT_CE);
+    eraObj[2] = dataPtr->mcLiterals[MCLIT_BCE2];
+    eraObj[3] = dataPtr->mcLiterals[MCLIT_CE2];
+    eraObj[4] = dataPtr->mcLiterals[MCLIT_BCE3];
+    eraObj[5] = dataPtr->mcLiterals[MCLIT_CE3];
+
+    if (eraObj[0] == NULL || eraObj[1] == NULL) {
+	return TCL_ERROR;
+    }
+
+    ret = ObjListSearch(info, &val, eraObj, 6,
+	minLen, maxLen);
+    if (ret != TCL_OK) {
+	return ret;
+    }
+
+    if (val & 1) {
+	yydate.isBce = 0;
+    } else {
+	yydate.isBce = 1;
+    }
+
+    return TCL_OK;
+}
+
+static int
+ClockScnToken_LocaleListMatcher_Proc(ClockFmtScnCmdArgs *opts,
+    DateInfo *info, ClockScanToken *tok)
+{
+    int ret, val;
+    int minLen, maxLen;
+    TclStrIdxTree *idxTree;
+
+    DetermineGreedySearchLen(info, tok, &minLen, &maxLen);
+
+    /* get or create tree in msgcat dict */
+
+    idxTree = ClockMCGetListIdxTree(opts, PTR2INT(tok->map->data) /* mcKey */);
+    if (idxTree == NULL) {
+	return TCL_ERROR;
+    }
+
+    ret = ClockStrIdxTreeSearch(info, idxTree, &val, minLen, maxLen);
+    if (ret != TCL_OK) {
+	return ret;
+    }
+
+    if (tok->map->offs > 0) {
+	*(int *)(((char *)info) + tok->map->offs) = --val;
+    }
+
+    return TCL_OK;
+}
+
+static int
+ClockScnToken_JDN_Proc(TCL_UNUSED(ClockFmtScnCmdArgs *),
+    DateInfo *info, ClockScanToken *tok)
+{
+    int minLen, maxLen;
+    const char *p = yyInput, *end; const char *s;
+    Tcl_WideInt intJD; int fractJD = 0, fractJDDiv = 1;
+
+    DetermineGreedySearchLen(info, tok, &minLen, &maxLen);
+
+    end = yyInput + maxLen;
+
+    /* currently positive astronomic dates only */
+    if (*p == '+' || *p == '-') { p++; };
+    s = p;
+    while (p < end && isdigit(UCHAR(*p))) {
+	p++;
+    }
+    if ( _str2wideInt(&intJD, s, p, (*yyInput != '-' ? 1 : -1)) != TCL_OK) {
+	return TCL_RETURN;
+    };
+    yyInput = p;
+    if (p >= end || *p++ != '.') { /* allow pure integer JDN */
+	/* by astronomical JD the seconds of day offs is 12 hours */
+	if (tok->map->offs) {
+	    goto done;
+	}
+	/* calendar JD */
+	yydate.julianDay = intJD;
+	return TCL_OK;
+    }
+    s = p;
+    while (p < end && isdigit(UCHAR(*p))) {
+    	fractJDDiv *= 10;
+	p++;
+    }
+    if ( _str2int(&fractJD, s, p, 1) != TCL_OK) {
+	return TCL_RETURN;
+    };
+    yyInput = p;
+
+done:
+    /*
+     * Build a date from julian day (integer and fraction).
+     * Note, astronomical JDN starts at noon in opposite to calendar julianday.
+     */
+
+    fractJD = (int)tok->map->offs /* 0 for calendar or 43200 for astro JD */
+	+ (int)((Tcl_WideInt)SECONDS_PER_DAY * fractJD / fractJDDiv);
+    if (fractJD > SECONDS_PER_DAY) {
+	fractJD %= SECONDS_PER_DAY;
+	intJD += 1;
+    }
+    yydate.secondOfDay = fractJD;
+    yydate.julianDay = intJD;
+
+    yydate.seconds =
+	-210866803200LL
+	+ ( SECONDS_PER_DAY * intJD )
+	+ ( fractJD );
+
+    info->flags |= CLF_POSIXSEC;
+
+    return TCL_OK;
+}
+
+static int
+ClockScnToken_TimeZone_Proc(ClockFmtScnCmdArgs *opts,
+    DateInfo *info, ClockScanToken *tok)
+{
+    int minLen, maxLen;
+    int len = 0;
+    const char *p = yyInput;
+    Tcl_Obj *tzObjStor = NULL;
+
+    DetermineGreedySearchLen(info, tok, &minLen, &maxLen);
+
+    /* numeric timezone */
+    if (*p == '+' || *p == '-') {
+	/* max chars in numeric zone = "+00:00:00" */
+    #define MAX_ZONE_LEN 9
+	char buf[MAX_ZONE_LEN + 1];
+	char *bp = buf;
+	*bp++ = *p++; len++;
+	if (maxLen > MAX_ZONE_LEN)
+	    maxLen = MAX_ZONE_LEN;
+	/* cumulate zone into buf without ':' */
+	while (len + 1 < maxLen) {
+	    if (!isdigit(UCHAR(*p))) break;
+	    *bp++ = *p++; len++;
+	    if (!isdigit(UCHAR(*p))) break;
+	    *bp++ = *p++; len++;
+	    if (len + 2 < maxLen) {
+		if (*p == ':') {
+		    p++; len++;
+		}
+	    }
+	}
+	*bp = '\0';
+
+	if (len < minLen) {
+	    return TCL_RETURN;
+	}
+    #undef MAX_ZONE_LEN
+
+	/* timezone */
+	tzObjStor = Tcl_NewStringObj(buf, bp-buf);
+    } else {
+	/* legacy (alnum) timezone like CEST, etc. */
+	if (maxLen > 4)
+	    maxLen = 4;
+	while (len < maxLen) {
+	    if ( (*p & 0x80)
+	      || (!isalpha(UCHAR(*p)) && !isdigit(UCHAR(*p)))
+	    ) {	      /* INTL: ISO only. */
+		break;
+	    }
+	    p++; len++;
+	}
+
+	if (len < minLen) {
+	    return TCL_RETURN;
+	}
+
+	/* timezone */
+	tzObjStor = Tcl_NewStringObj(yyInput, p-yyInput);
+
+	/* convert using dict */
+    }
+
+    /* try to apply new time zone */
+    Tcl_IncrRefCount(tzObjStor);
+
+    opts->timezoneObj = ClockSetupTimeZone(opts->clientData, opts->interp,
+	tzObjStor);
+
+    Tcl_DecrRefCount(tzObjStor);
+    if (opts->timezoneObj == NULL) {
+	return TCL_ERROR;
+    }
+
+    yyInput += len;
+
+    return TCL_OK;
+}
+
+static int
+ClockScnToken_StarDate_Proc(TCL_UNUSED(ClockFmtScnCmdArgs *),
+    DateInfo *info, ClockScanToken *tok)
+{
+    int minLen, maxLen;
+    const char *p = yyInput, *end; const char *s;
+    int year, fractYear, fractDayDiv, fractDay;
+    static const char *stardatePref = "stardate ";
+
+    DetermineGreedySearchLen(info, tok, &minLen, &maxLen);
+
+    end = yyInput + maxLen;
+
+    /* stardate string */
+    p = TclUtfFindEqualNCInLwr(p, end, stardatePref, stardatePref + 9, &s);
+    if (p >= end || p - yyInput < 9) {
+	return TCL_RETURN;
+    }
+    /* bypass spaces */
+    while (p < end && isspace(UCHAR(*p))) {
+	p++;
+    }
+    if (p >= end) {
+	return TCL_RETURN;
+    }
+    /* currently positive stardate only */
+    if (*p == '+') { p++; };
+    s = p;
+    while (p < end && isdigit(UCHAR(*p))) {
+	p++;
+    }
+    if (p >= end || p - s < 4) {
+	return TCL_RETURN;
+    }
+    if ( _str2int(&year, s, p-3, 1) != TCL_OK
+      || _str2int(&fractYear, p-3, p, 1) != TCL_OK) {
+	return TCL_RETURN;
+    };
+    if (*p++ != '.') {
+	return TCL_RETURN;
+    }
+    s = p;
+    fractDayDiv = 1;
+    while (p < end && isdigit(UCHAR(*p))) {
+	fractDayDiv *= 10;
+	p++;
+    }
+    if ( _str2int(&fractDay, s, p, 1) != TCL_OK) {
+	return TCL_RETURN;
+    };
+    yyInput = p;
+
+    /* Build a date from year and fraction. */
+
+    yydate.year = year + RODDENBERRY;
+    yydate.isBce = 0;
+    yydate.gregorian = 1;
+
+    if (IsGregorianLeapYear(&yydate)) {
+	fractYear *= 366;
+    } else {
+	fractYear *= 365;
+    }
+    yydate.dayOfYear = fractYear / 1000 + 1;
+    if (fractYear % 1000 >= 500) {
+	yydate.dayOfYear++;
+    }
+
+    GetJulianDayFromEraYearDay(&yydate, GREGORIAN_CHANGE_DATE);
+
+    yydate.localSeconds =
+	-210866803200LL
+	+ ( SECONDS_PER_DAY * yydate.julianDay )
+	+ ( SECONDS_PER_DAY * fractDay / fractDayDiv );
+
+    return TCL_OK;
+}
+
+static const char *ScnSTokenMapIndex =
+    "dmbyYHMSpJjCgGVazUsntQ";
+static ClockScanTokenMap ScnSTokenMap[] = {
+    /* %d %e */
+    {CTOKT_INT, CLF_DAYOFMONTH, 0, 1, 2, offsetof(DateInfo, date.dayOfMonth),
+	NULL, NULL},
+    /* %m %N */
+    {CTOKT_INT, CLF_MONTH, 0, 1, 2, offsetof(DateInfo, date.month),
+	NULL, NULL},
+    /* %b %B %h */
+    {CTOKT_PARSER, CLF_MONTH, 0, 0, 0xffff, 0,
+	    ClockScnToken_Month_Proc, NULL},
+    /* %y */
+    {CTOKT_INT, CLF_YEAR, 0, 1, 2, offsetof(DateInfo, date.year),
+	NULL, NULL},
+    /* %Y */
+    {CTOKT_INT, CLF_YEAR | CLF_CENTURY, 0, 4, 4, offsetof(DateInfo, date.year),
+	NULL, NULL},
+    /* %H %k %I %l */
+    {CTOKT_INT, CLF_TIME, 0, 1, 2, offsetof(DateInfo, date.hour),
+	NULL, NULL},
+    /* %M */
+    {CTOKT_INT, CLF_TIME, 0, 1, 2, offsetof(DateInfo, date.minutes),
+	NULL, NULL},
+    /* %S */
+    {CTOKT_INT, CLF_TIME, 0, 1, 2, offsetof(DateInfo, date.secondOfMin),
+	NULL, NULL},
+    /* %p %P */
+    {CTOKT_PARSER, 0, 0, 0, 0xffff, 0,
+	ClockScnToken_amPmInd_Proc, NULL},
+    /* %J */
+    {CTOKT_WIDE, CLF_JULIANDAY | CLF_SIGNED, 0, 1, 0xffff, offsetof(DateInfo, date.julianDay),
+	NULL, NULL},
+    /* %j */
+    {CTOKT_INT, CLF_DAYOFYEAR, 0, 1, 3, offsetof(DateInfo, date.dayOfYear),
+	NULL, NULL},
+    /* %C */
+    {CTOKT_INT, CLF_CENTURY|CLF_ISO8601CENTURY, 0, 1, 2, offsetof(DateInfo, dateCentury),
+	NULL, NULL},
+    /* %g */
+    {CTOKT_INT, CLF_ISO8601YEAR, 0, 2, 2, offsetof(DateInfo, date.iso8601Year),
+	NULL, NULL},
+    /* %G */
+    {CTOKT_INT, CLF_ISO8601YEAR | CLF_ISO8601CENTURY, 0, 4, 4, offsetof(DateInfo, date.iso8601Year),
+	NULL, NULL},
+    /* %V */
+    {CTOKT_INT, CLF_ISO8601WEAK, 0, 1, 2, offsetof(DateInfo, date.iso8601Week),
+	NULL, NULL},
+    /* %a %A %u %w */
+    {CTOKT_PARSER, CLF_DAYOFWEEK, 0, 0, 0xffff, 0,
+	ClockScnToken_DayOfWeek_Proc, NULL},
+    /* %z %Z */
+    {CTOKT_PARSER, CLF_OPTIONAL, 0, 0, 0xffff, 0,
+	ClockScnToken_TimeZone_Proc, NULL},
+    /* %U %W */
+    {CTOKT_INT, CLF_OPTIONAL, 0, 1, 2, 0, /* currently no capture, parse only token */
+	NULL, NULL},
+    /* %s */
+    {CTOKT_WIDE, CLF_POSIXSEC | CLF_SIGNED, 0, 1, 0xffff, offsetof(DateInfo, date.seconds),
+	NULL, NULL},
+    /* %n */
+    {CTOKT_CHAR, 0, 0, 1, 1, 0, NULL, "\n"},
+    /* %t */
+    {CTOKT_CHAR, 0, 0, 1, 1, 0, NULL, "\t"},
+    /* %Q */
+    {CTOKT_PARSER, CLF_LOCALSEC, 0, 16, 30, 0,
+	ClockScnToken_StarDate_Proc, NULL},
+};
+static const char *ScnSTokenMapAliasIndex[2] = {
+    "eNBhkIlPAuwZW",
+    "dmbbHHHpaaazU"
+};
+
+static const char *ScnETokenMapIndex =
+    "EJjys";
+static ClockScanTokenMap ScnETokenMap[] = {
+    /* %EE */
+    {CTOKT_PARSER, 0, 0, 0, 0xffff, offsetof(DateInfo, date.year),
+	ClockScnToken_LocaleERA_Proc, (void *)MCLIT_LOCALE_NUMERALS},
+    /* %EJ */
+    {CTOKT_PARSER, CLF_JULIANDAY | CLF_SIGNED, 0, 1, 0xffff, 0, /* calendar JDN starts at midnight */
+	ClockScnToken_JDN_Proc, NULL},
+    /* %Ej */
+    {CTOKT_PARSER, CLF_JULIANDAY | CLF_SIGNED, 0, 1, 0xffff, (SECONDS_PER_DAY/2), /* astro JDN starts at noon */
+	ClockScnToken_JDN_Proc, NULL},
+    /* %Ey */
+    {CTOKT_PARSER, 0, 0, 0, 0xffff, 0, /* currently no capture, parse only token */
+	ClockScnToken_LocaleListMatcher_Proc, (void *)MCLIT_LOCALE_NUMERALS},
+    /* %Es */
+    {CTOKT_WIDE, CLF_LOCALSEC | CLF_SIGNED, 0, 1, 0xffff, offsetof(DateInfo, date.localSeconds),
+	NULL, NULL},
+};
+static const char *ScnETokenMapAliasIndex[2] = {
+    "",
+    ""
+};
+
+static const char *ScnOTokenMapIndex =
+    "dmyHMSu";
+static ClockScanTokenMap ScnOTokenMap[] = {
+    /* %Od %Oe */
+    {CTOKT_PARSER, CLF_DAYOFMONTH, 0, 0, 0xffff, offsetof(DateInfo, date.dayOfMonth),
+	ClockScnToken_LocaleListMatcher_Proc, (void *)MCLIT_LOCALE_NUMERALS},
+    /* %Om */
+    {CTOKT_PARSER, CLF_MONTH, 0, 0, 0xffff, offsetof(DateInfo, date.month),
+	ClockScnToken_LocaleListMatcher_Proc, (void *)MCLIT_LOCALE_NUMERALS},
+    /* %Oy */
+    {CTOKT_PARSER, CLF_YEAR, 0, 0, 0xffff, offsetof(DateInfo, date.year),
+	ClockScnToken_LocaleListMatcher_Proc, (void *)MCLIT_LOCALE_NUMERALS},
+    /* %OH %Ok %OI %Ol */
+    {CTOKT_PARSER, CLF_TIME, 0, 0, 0xffff, offsetof(DateInfo, date.hour),
+	ClockScnToken_LocaleListMatcher_Proc, (void *)MCLIT_LOCALE_NUMERALS},
+    /* %OM */
+    {CTOKT_PARSER, CLF_TIME, 0, 0, 0xffff, offsetof(DateInfo, date.minutes),
+	ClockScnToken_LocaleListMatcher_Proc, (void *)MCLIT_LOCALE_NUMERALS},
+    /* %OS */
+    {CTOKT_PARSER, CLF_TIME, 0, 0, 0xffff, offsetof(DateInfo, date.secondOfMin),
+	ClockScnToken_LocaleListMatcher_Proc, (void *)MCLIT_LOCALE_NUMERALS},
+    /* %Ou Ow */
+    {CTOKT_PARSER, CLF_DAYOFWEEK, 0, 0, 0xffff, 0,
+	ClockScnToken_DayOfWeek_Proc, (void *)MCLIT_LOCALE_NUMERALS},
+};
+static const char *ScnOTokenMapAliasIndex[2] = {
+    "ekIlw",
+    "dHHHu"
+};
+
+/* Token map reserved for CTOKT_SPACE */
+static ClockScanTokenMap ScnSpaceTokenMap = {
+    CTOKT_SPACE,  0, 0, 1, 1, 0,
+	NULL, NULL
+};
+
+static ClockScanTokenMap ScnWordTokenMap = {
+    CTOKT_WORD,	   0, 0, 1, 1, 0,
+	NULL, NULL
+};
+
+
+static inline unsigned int
+EstimateTokenCount(
+    const char *fmt,
+    const char *end)
+{
+    const char *p = fmt;
+    unsigned int tokcnt;
+    /* estimate token count by % char and format length */
+    tokcnt = 0;
+    while (p <= end) {
+	if (*p++ == '%') {
+	    tokcnt++;
+	    p++;
+	}
+    }
+    p = fmt + tokcnt * 2;
+    if (p < end) {
+	if ((unsigned int)(end - p) < tokcnt) {
+	    tokcnt += (end - p);
+	} else {
+	    tokcnt += tokcnt;
+	}
+    }
+    return ++tokcnt;
+}
+
+#define AllocTokenInChain(tok, chain, tokCnt, type) \
+    if (++(tok) >= (chain) + (tokCnt)) { \
+	chain = (type)Tcl_Realloc((char *)(chain), \
+	    (tokCnt + CLOCK_MIN_TOK_CHAIN_BLOCK_SIZE) * sizeof(*(tok))); \
+	if ((chain) == NULL) { goto done; }; \
+	(tok) = (chain) + (tokCnt); \
+	(tokCnt) += CLOCK_MIN_TOK_CHAIN_BLOCK_SIZE; \
+    } \
+    memset(tok, 0, sizeof(*(tok)));
+
+/*
+ *----------------------------------------------------------------------
+ */
+ClockFmtScnStorage *
+ClockGetOrParseScanFormat(
+    Tcl_Interp *interp,		/* Tcl interpreter */
+    Tcl_Obj    *formatObj)	/* Format container */
+{
+    ClockFmtScnStorage *fss;
+
+    fss = Tcl_GetClockFrmScnFromObj(interp, formatObj);
+    if (fss == NULL) {
+	return NULL;
+    }
+
+    /* if format (scnTok) already tokenized */
+    if (fss->scnTok != NULL) {
+	return fss;
+    }
+
+    Tcl_MutexLock(&ClockFmtMutex);
+
+    /* first time scanning - tokenize format */
+    if (fss->scnTok == NULL) {
+	ClockScanToken *tok, *scnTok;
+	unsigned int tokCnt;
+	const char *p, *e, *cp;
+
+	e = p = HashEntry4FmtScn(fss)->key.string;
+	e += strlen(p);
+
+	/* estimate token count by % char and format length */
+	fss->scnTokC = EstimateTokenCount(p, e);
+
+	fss->scnSpaceCount = 0;
+
+	scnTok = tok = (ClockScanToken *)Tcl_Alloc(sizeof(*tok) * fss->scnTokC);
+	memset(tok, 0, sizeof(*(tok)));
+	tokCnt = 1;
+	while (p < e) {
+	    switch (*p) {
+	    case '%':
+	    if (1) {
+		ClockScanTokenMap * scnMap = ScnSTokenMap;
+		const char *mapIndex =	ScnSTokenMapIndex,
+			  **aliasIndex = ScnSTokenMapAliasIndex;
+		if (p+1 >= e) {
+		    goto word_tok;
+		}
+		p++;
+		/* try to find modifier: */
+		switch (*p) {
+		case '%':
+		    /* begin new word token - don't join with previous word token,
+		     * because current mapping should be "...%%..." -> "...%..." */
+		    tok->map = &ScnWordTokenMap;
+		    tok->tokWord.start = p;
+		    tok->tokWord.end = p+1;
+		    AllocTokenInChain(tok, scnTok, fss->scnTokC, ClockScanToken *); tokCnt++;
+		    p++;
+		    continue;
+		break;
+		case 'E':
+		    scnMap = ScnETokenMap,
+		    mapIndex =	ScnETokenMapIndex,
+		    aliasIndex = ScnETokenMapAliasIndex;
+		    p++;
+		break;
+		case 'O':
+		    scnMap = ScnOTokenMap,
+		    mapIndex = ScnOTokenMapIndex,
+		    aliasIndex = ScnOTokenMapAliasIndex;
+		    p++;
+		break;
+		}
+		/* search direct index */
+		cp = strchr(mapIndex, *p);
+		if (!cp || *cp == '\0') {
+		    /* search wrapper index (multiple chars for same token) */
+		    cp = strchr(aliasIndex[0], *p);
+		    if (!cp || *cp == '\0') {
+			p--; if (scnMap != ScnSTokenMap) p--;
+			goto word_tok;
+		    }
+		    cp = strchr(mapIndex, aliasIndex[1][cp - aliasIndex[0]]);
+		    if (!cp || *cp == '\0') { /* unexpected, but ... */
+		    #ifdef DEBUG
+			Tcl_Panic("token \"%c\" has no map in wrapper resolver", *p);
+		    #endif
+			p--; if (scnMap != ScnSTokenMap) p--;
+			goto word_tok;
+		    }
+		}
+		tok->map = &scnMap[cp - mapIndex];
+		tok->tokWord.start = p;
+
+		/* calculate look ahead value by standing together tokens */
+		if (tok > scnTok) {
+		    ClockScanToken     *prevTok = tok - 1;
+
+		    while (prevTok >= scnTok) {
+			if (prevTok->map->type != tok->map->type) {
+			    break;
+			}
+			prevTok->lookAhMin += tok->map->minSize;
+			prevTok->lookAhMax += tok->map->maxSize;
+			prevTok->lookAhTok++;
+			prevTok--;
+		    }
+		}
+
+		/* increase space count used in format */
+		if ( tok->map->type == CTOKT_CHAR
+		  && isspace(UCHAR(*((char *)tok->map->data)))
+		) {
+		    fss->scnSpaceCount++;
+		}
+
+		/* next token */
+		AllocTokenInChain(tok, scnTok, fss->scnTokC, ClockScanToken *); tokCnt++;
+		p++;
+		continue;
+	    }
+	    break;
+	    default:
+	    if ( *p == ' ' || isspace(UCHAR(*p)) ) {
+		tok->map = &ScnSpaceTokenMap;
+		tok->tokWord.start = p++;
+		while (p < e && isspace(UCHAR(*p))) {
+		    p++;
+		}
+		tok->tokWord.end = p;
+		/* increase space count used in format */
+		fss->scnSpaceCount++;
+		/* next token */
+		AllocTokenInChain(tok, scnTok, fss->scnTokC, ClockScanToken *); tokCnt++;
+		continue;
+	    }
+word_tok:
+	    if (1) {
+		ClockScanToken	 *wordTok = tok;
+		if (tok > scnTok && (tok-1)->map == &ScnWordTokenMap) {
+		    wordTok = tok-1;
+		}
+		/* new word token */
+		if (wordTok == tok) {
+		    wordTok->tokWord.start = p;
+		    wordTok->map = &ScnWordTokenMap;
+		    AllocTokenInChain(tok, scnTok, fss->scnTokC, ClockScanToken *); tokCnt++;
+		}
+		if (isspace(UCHAR(*p))) {
+		    fss->scnSpaceCount++;
+		}
+		p = Tcl_UtfNext(p);
+		wordTok->tokWord.end = p;
+	    }
+	    break;
+	    }
+	}
+
+	/* calculate end distance value for each tokens */
+	if (tok > scnTok) {
+	    unsigned int	endDist = 0;
+	    ClockScanToken     *prevTok = tok-1;
+
+	    while (prevTok >= scnTok) {
+		prevTok->endDistance = endDist;
+		if (prevTok->map->type != CTOKT_WORD) {
+		    endDist += prevTok->map->minSize;
+		} else {
+		    endDist += prevTok->tokWord.end - prevTok->tokWord.start;
+		}
+		prevTok--;
+	    }
+	}
+
+	/* correct count of real used tokens and free mem if desired
+	 * (1 is acceptable delta to prevent memory fragmentation) */
+	if (fss->scnTokC > tokCnt + (CLOCK_MIN_TOK_CHAIN_BLOCK_SIZE / 2)) {
+	    if ( (tok = (ClockScanToken *)Tcl_Realloc(scnTok, tokCnt * sizeof(*tok))) != NULL ) {
+		scnTok = tok;
+	    }
+	}
+
+	/* now we're ready - assign now to storage (note the threaded race condition) */
+	fss->scnTok = scnTok;
+	fss->scnTokC = tokCnt;
+    }
+done:
+    Tcl_MutexUnlock(&ClockFmtMutex);
+
+    return fss;
+}
+
+/*
+ *----------------------------------------------------------------------
+ */
+int
+ClockScan(
+    DateInfo *info,	/* Date fields used for parsing & converting */
+    Tcl_Obj *strObj,		/* String containing the time to scan */
+    ClockFmtScnCmdArgs *opts)	/* Command options */
+{
+    ClockClientData *dataPtr = (ClockClientData *)opts->clientData;
+    ClockFmtScnStorage	*fss;
+    ClockScanToken	*tok;
+    ClockScanTokenMap	*map;
+    const char *p, *x, *end;
+    unsigned short int	 flags = 0;
+    int ret = TCL_ERROR;
+
+    /* get localized format */
+    if (ClockLocalizeFormat(opts) == NULL) {
+	return TCL_ERROR;
+    }
+
+    if ( !(fss = ClockGetOrParseScanFormat(opts->interp, opts->formatObj))
+      || !(tok = fss->scnTok)
+    ) {
+	return TCL_ERROR;
+    }
+
+    /* prepare parsing */
+
+    yyMeridian = MER24;
+
+    p = TclGetString(strObj);
+    end = p + strObj->length;
+    /* in strict mode - bypass spaces at begin / end only (not between tokens) */
+    if (opts->flags & CLF_STRICT) {
+	while (p < end && isspace(UCHAR(*p))) {
+	    p++;
+	}
+    }
+    yyInput = p;
+    /* look ahead to count spaces (bypass it by count length and distances) */
+    x = end;
+    while (p < end) {
+	if (isspace(UCHAR(*p))) {
+	    x = ++p; /* after first space in space block */
+	    yySpaceCount++;
+	    while (p < end && isspace(UCHAR(*p))) {
+		p++;
+		yySpaceCount++;
+	    }
+	    continue;
+	}
+	x = end;
+	p++;
+    }
+    /* ignore more as 1 space at end */
+    yySpaceCount -= (end - x);
+    end = x;
+    /* ignore mandatory spaces used in format */
+    yySpaceCount -= fss->scnSpaceCount;
+    if (yySpaceCount < 0) {
+	yySpaceCount = 0;
+    }
+    info->dateStart = p = yyInput;
+    info->dateEnd = end;
+
+    /* parse string */
+    for (; tok->map != NULL; tok++) {
+	map = tok->map;
+	/* bypass spaces at begin of input before parsing each token */
+	if ( !(opts->flags & CLF_STRICT)
+	  && ( map->type != CTOKT_SPACE
+	    && map->type != CTOKT_WORD
+	    && map->type != CTOKT_CHAR )
+	) {
+	    while (p < end && isspace(UCHAR(*p))) {
+		yySpaceCount--;
+		p++;
+	    }
+	}
+	yyInput = p;
+	/* end of input string */
+	if (p >= end) {
+	    break;
+	}
+	switch (map->type)
+	{
+	case CTOKT_INT:
+	case CTOKT_WIDE:
+	if (1) {
+	    int minLen, size;
+	    int sign = 1;
+	    if (map->flags & CLF_SIGNED) {
+		if (*p == '+') { yyInput = ++p; }
+		else
+		if (*p == '-') { yyInput = ++p; sign = -1; };
+	    }
+
+	    DetermineGreedySearchLen(info, tok, &minLen, &size);
+
+	    if (size < map->minSize) {
+		/* missing input -> error */
+		if ((map->flags & CLF_OPTIONAL)) {
+		    continue;
+		}
+		goto not_match;
+	    }
+	    /* string 2 number, put number into info structure by offset */
+	    if (map->offs) {
+		p = yyInput; x = p + size;
+		if (map->type == CTOKT_INT) {
+		    if (_str2int((int *)(((char *)info) + map->offs),
+			    p, x, sign) != TCL_OK) {
+			goto overflow;
+		    }
+		    p = x;
+		} else {
+		    if (_str2wideInt((Tcl_WideInt *)(((char *)info) + map->offs),
+			    p, x, sign) != TCL_OK) {
+			goto overflow;
+		    }
+		    p = x;
+		}
+		flags = (flags & ~map->clearFlags) | map->flags;
+	    }
+	}
+	break;
+	case CTOKT_PARSER:
+	    switch (map->parser(opts, info, tok)) {
+		case TCL_OK:
+		break;
+		case TCL_RETURN:
+		    if ((map->flags & CLF_OPTIONAL)) {
+			yyInput = p;
+			continue;
+		    }
+		    goto not_match;
+		break;
+		default:
+		    goto done;
+		break;
+	    };
+	    /* decrement count for possible spaces in match */
+	    while (p < yyInput) {
+		if (isspace(UCHAR(*p))) {
+		    yySpaceCount--;
+		}
+		p++;
+	    }
+	    p = yyInput;
+	    flags = (flags & ~map->clearFlags) | map->flags;
+	break;
+	case CTOKT_SPACE:
+	    /* at least one space */
+	    if (!isspace(UCHAR(*p))) {
+		/* unmatched -> error */
+		goto not_match;
+	    }
+	    /* don't decrement yySpaceCount by regular (first expected space),
+	     * already considered above with fss->scnSpaceCount */;
+	    p++;
+	    while (p < end && isspace(UCHAR(*p))) {
+		yySpaceCount--;
+		p++;
+	    }
+	break;
+	case CTOKT_WORD:
+	    x = FindWordEnd(tok, p, end);
+	    if (!x) {
+		/* no match -> error */
+		goto not_match;
+	    }
+	    p = x;
+	break;
+	case CTOKT_CHAR:
+	    x = (char *)map->data;
+	    if (*x != *p) {
+		/* no match -> error */
+		goto not_match;
+	    }
+	    if (isspace(UCHAR(*x))) {
+		yySpaceCount--;
+	    }
+	    p++;
+	break;
+	}
+    }
+    /* check end was reached */
+    if (p < end) {
+	/* in non-strict mode bypass spaces at end of input */
+	if ( !(opts->flags & CLF_STRICT) && isspace(UCHAR(*p)) ) {
+	    p++;
+	    while (p < end && isspace(UCHAR(*p))) {
+		p++;
+	    }
+	}
+	/* something after last token - wrong format */
+	if (p < end) {
+	    goto not_match;
+	}
+    }
+    /* end of string, check only optional tokens at end, otherwise - not match */
+    while (tok->map != NULL) {
+	if (!(opts->flags & CLF_STRICT) && (tok->map->type == CTOKT_SPACE)) {
+	    tok++;
+	    if (tok->map == NULL) {
+		/* no tokens anymore - trailing spaces are mandatory */
+		goto not_match;
+	    }
+	}
+	if (!(tok->map->flags & CLF_OPTIONAL)) {
+	    goto not_match;
+	}
+	tok++;
+    }
+
+    /*
+     * Invalidate result
+     */
+    flags |= info->flags;
+
+    /* seconds token (%s) take precedence over all other tokens */
+    if ((opts->flags & CLF_EXTENDED) || !(flags & CLF_POSIXSEC)) {
+	if (flags & CLF_DATE) {
+
+	    if (!(flags & CLF_JULIANDAY)) {
+		info->flags |= CLF_ASSEMBLE_SECONDS|CLF_ASSEMBLE_JULIANDAY;
+
+		/* dd precedence below ddd */
+		switch (flags & (CLF_MONTH|CLF_DAYOFYEAR|CLF_DAYOFMONTH)) {
+		    case (CLF_DAYOFYEAR|CLF_DAYOFMONTH):
+		    /* miss month: ddd over dd (without month) */
+		    flags &= ~CLF_DAYOFMONTH;
+		    /* fallthrough */
+		    case (CLF_DAYOFYEAR):
+		    /* ddd over naked weekday */
+		    if (!(flags & CLF_ISO8601YEAR)) {
+			flags &= ~CLF_ISO8601WEAK;
+		    }
+		    break;
+		    case (CLF_MONTH|CLF_DAYOFYEAR|CLF_DAYOFMONTH):
+		    /* both available: mmdd over ddd */
+		    case (CLF_MONTH|CLF_DAYOFMONTH):
+		    case (CLF_DAYOFMONTH):
+		    /* mmdd / dd over naked weekday */
+		    if (!(flags & CLF_ISO8601YEAR)) {
+			flags &= ~CLF_ISO8601WEAK;
+		    }
+		    break;
+		    /* neither mmdd nor ddd available */
+		    case 0:
+		    /* but we have day of the week, which can be used */
+		    if (flags & CLF_DAYOFWEEK) {
+			/* prefer week based calculation of julianday */
+			flags |= CLF_ISO8601WEAK;
+		    }
+		}
+
+		/* YearWeekDay below YearMonthDay */
+		if ( (flags & CLF_ISO8601WEAK)
+		  && ( (flags & (CLF_YEAR|CLF_DAYOFYEAR)) == (CLF_YEAR|CLF_DAYOFYEAR)
+		    || (flags & (CLF_YEAR|CLF_DAYOFMONTH|CLF_MONTH)) == (CLF_YEAR|CLF_DAYOFMONTH|CLF_MONTH)
+		  )
+		) {
+		    /* yy precedence below yyyy */
+		    if (!(flags & CLF_ISO8601CENTURY) && (flags & CLF_CENTURY)) {
+			/* normally precedence of ISO is higher, but no century - so put it down */
+			flags &= ~CLF_ISO8601WEAK;
+		    }
+		    else
+		    /* yymmdd or yyddd over naked weekday */
+		    if (!(flags & CLF_ISO8601YEAR)) {
+			flags &= ~CLF_ISO8601WEAK;
+		    }
+		}
+
+		if ( (flags & CLF_YEAR) ) {
+		    if (yyYear < 100) {
+			if (!(flags & CLF_CENTURY)) {
+			    if (yyYear >= dataPtr->yearOfCenturySwitch) {
+				yyYear -= 100;
+			    }
+			    yyYear += dataPtr->currentYearCentury;
+			} else {
+			    yyYear += info->dateCentury * 100;
+			}
+		    }
+		}
+		if ( (flags & (CLF_ISO8601WEAK|CLF_ISO8601YEAR)) ) {
+		    if ((flags & (CLF_ISO8601YEAR|CLF_YEAR)) == CLF_YEAR) {
+		    	/* for calculations expected iso year */
+			info->date.iso8601Year = yyYear;
+		    }
+		    else
+		    if (info->date.iso8601Year < 100) {
+			if (!(flags & CLF_ISO8601CENTURY)) {
+			    if (info->date.iso8601Year >= dataPtr->yearOfCenturySwitch) {
+				info->date.iso8601Year -= 100;
+			    }
+			    info->date.iso8601Year += dataPtr->currentYearCentury;
+			} else {
+			    info->date.iso8601Year += info->dateCentury * 100;
+			}
+		    }
+		    if ((flags & (CLF_ISO8601YEAR|CLF_YEAR)) == CLF_ISO8601YEAR) {
+		    	/* for calculations expected year (e. g. CLF_ISO8601WEAK not set) */
+			yyYear = info->date.iso8601Year;
+		    }
+		}
+	    }
+	}
+
+	/* if no time - reset time */
+	if (!(flags & (CLF_TIME|CLF_LOCALSEC|CLF_POSIXSEC))) {
+	    info->flags |= CLF_ASSEMBLE_SECONDS;
+	    yydate.localSeconds = 0;
+	}
+
+	if (flags & CLF_TIME) {
+	    info->flags |= CLF_ASSEMBLE_SECONDS;
+	    yySecondOfDay = ToSeconds(yyHour, yyMinutes,
+				yySeconds, yyMeridian);
+	} else
+	if (!(flags & (CLF_LOCALSEC|CLF_POSIXSEC))) {
+	    info->flags |= CLF_ASSEMBLE_SECONDS;
+	    yySecondOfDay = yydate.localSeconds % SECONDS_PER_DAY;
+	}
+    }
+
+    /* tell caller which flags were set */
+    info->flags |= flags;
+
+    ret = TCL_OK;
+    goto done;
+
+overflow:
+
+    Tcl_SetObjResult(opts->interp, Tcl_NewStringObj("integer value too large to represent",
+	-1));
+    Tcl_SetErrorCode(opts->interp, "CLOCK", "dateTooLarge", (char *)NULL);
+    goto done;
+
+not_match:
+
+  #if 1
+    Tcl_SetObjResult(opts->interp, Tcl_NewStringObj("input string does not match supplied format",
+	-1));
+  #else
+	/* to debug where exactly scan breaks */
+    Tcl_SetObjResult(opts->interp, Tcl_ObjPrintf(
+	"input string \"%s\" does not match supplied format \"%s\","
+	" locale \"%s\" - token \"%s\"",
+	info->dateStart, HashEntry4FmtScn(fss)->key.string,
+        Tcl_GetString(opts->localeObj),
+        tok && tok->tokWord.start ? tok->tokWord.start : "NULL"));
+  #endif
+    Tcl_SetErrorCode(opts->interp, "CLOCK", "badInputString", (char *)NULL);
+
+done:
+
+    return ret;
+}
+
+#define FrmResultIsAllocated(dateFmt) \
+    (dateFmt->resEnd - dateFmt->resMem > MIN_FMT_RESULT_BLOCK_ALLOC)
+
+static inline int
+FrmResultAllocate(
+    DateFormat *dateFmt,
+    int len)
+{
+    int needed = dateFmt->output + len - dateFmt->resEnd;
+    if (needed >= 0) { /* >= 0 - regards NTS zero */
+	int newsize = dateFmt->resEnd - dateFmt->resMem
+		    + needed + MIN_FMT_RESULT_BLOCK_ALLOC*2;
+	char *newRes;
+	/* differentiate between stack and memory */
+	if (!FrmResultIsAllocated(dateFmt)) {
+	    newRes = (char *)Tcl_Alloc(newsize);
+	    if (newRes == NULL) {
+		return TCL_ERROR;
+	    }
+	    memcpy(newRes, dateFmt->resMem, dateFmt->output - dateFmt->resMem);
+	} else {
+	    newRes = (char *)Tcl_Realloc(dateFmt->resMem, newsize);
+	    if (newRes == NULL) {
+		return TCL_ERROR;
+	    }
+	}
+	dateFmt->output = newRes + (dateFmt->output - dateFmt->resMem);
+	dateFmt->resMem = newRes;
+	dateFmt->resEnd = newRes + newsize;
+    }
+    return TCL_OK;
+}
+
+static int
+ClockFmtToken_HourAMPM_Proc(
+    TCL_UNUSED(ClockFmtScnCmdArgs *),
+    TCL_UNUSED(DateFormat *),
+    TCL_UNUSED(ClockFormatToken *),
+    int *val)
+{
+    *val = ( ( *val + SECONDS_PER_DAY - 3600 ) / 3600 ) % 12 + 1;
+    return TCL_OK;
+}
+
+static int
+ClockFmtToken_AMPM_Proc(
+    ClockFmtScnCmdArgs *opts,
+    DateFormat *dateFmt,
+    ClockFormatToken *tok,
+    int *val)
+{
+    Tcl_Obj *mcObj;
+    const char *s;
+    Tcl_Size len;
+
+    if (*val < (SECONDS_PER_DAY / 2)) {
+	mcObj = ClockMCGet(opts, MCLIT_AM);
+    } else {
+	mcObj = ClockMCGet(opts, MCLIT_PM);
+    }
+    if (mcObj == NULL) {
+	return TCL_ERROR;
+    }
+    s = TclGetStringFromObj(mcObj, &len);
+    if (FrmResultAllocate(dateFmt, len) != TCL_OK) { return TCL_ERROR; };
+    memcpy(dateFmt->output, s, len + 1);
+    if (*tok->tokWord.start == 'p') {
+	len = Tcl_UtfToUpper(dateFmt->output);
+    }
+    dateFmt->output += len;
+
+    return TCL_OK;
+}
+
+static int
+ClockFmtToken_StarDate_Proc(
+    TCL_UNUSED(ClockFmtScnCmdArgs *),
+    DateFormat *dateFmt,
+    TCL_UNUSED(ClockFormatToken *),
+    TCL_UNUSED(int *))
+{
+    int fractYear;
+    /* Get day of year, zero based */
+    int v = dateFmt->date.dayOfYear - 1;
+
+    /* Convert day of year to a fractional year */
+    if (IsGregorianLeapYear(&dateFmt->date)) {
+	fractYear = 1000 * v / 366;
+    } else {
+	fractYear = 1000 * v / 365;
+    }
+
+    /* Put together the StarDate as "Stardate %02d%03d.%1d" */
+    if (FrmResultAllocate(dateFmt, 30) != TCL_OK) { return TCL_ERROR; };
+    memcpy(dateFmt->output, "Stardate ", 9);
+    dateFmt->output += 9;
+    dateFmt->output = _itoaw(dateFmt->output,
+	dateFmt->date.year - RODDENBERRY, '0', 2);
+    dateFmt->output = _itoaw(dateFmt->output,
+	fractYear, '0', 3);
+    *dateFmt->output++ = '.';
+    /* be sure positive after decimal point (note: clock-value can be negative) */
+    v = dateFmt->date.secondOfDay / ( SECONDS_PER_DAY / 10 );
+    if (v < 0) v = 10 + v;
+    dateFmt->output = _itoaw(dateFmt->output, v, '0', 1);
+
+    return TCL_OK;
+}
+static int
+ClockFmtToken_WeekOfYear_Proc(
+    TCL_UNUSED(ClockFmtScnCmdArgs *),
+    DateFormat *dateFmt,
+    ClockFormatToken *tok,
+    int *val)
+{
+    int dow = dateFmt->date.dayOfWeek;
+
+    if (*tok->tokWord.start == 'U') {
+	if (dow == 7) {
+	    dow = 0;
+	}
+	dow++;
+    }
+    *val = ( dateFmt->date.dayOfYear - dow + 7 ) / 7;
+    return TCL_OK;
+}
+static int
+ClockFmtToken_JDN_Proc(
+    TCL_UNUSED(ClockFmtScnCmdArgs *),
+    DateFormat *dateFmt,
+    ClockFormatToken *tok,
+    TCL_UNUSED(int *))
+{
+    Tcl_WideInt intJD = dateFmt->date.julianDay;
+    int fractJD;
+
+    /* Convert to JDN parts (regarding start offset) and time fraction */
+    fractJD = dateFmt->date.secondOfDay
+	- (int)tok->map->offs; /* 0 for calendar or 43200 for astro JD */
+    if (fractJD < 0) {
+    	intJD--;
+	fractJD += SECONDS_PER_DAY;
+    }
+    if (fractJD && intJD < 0) { /* avoid jump over 0, by negative JD's */
+	intJD++;
+	if (intJD == 0) {
+	    /* -0.0 / -0.9 has zero integer part, so append "-" extra */
+	    if (FrmResultAllocate(dateFmt, 1) != TCL_OK) { return TCL_ERROR; };
+	    *dateFmt->output++ = '-';
+	}
+	/* and inverse seconds of day, -0(75) -> -0.25 as float */
+	fractJD = SECONDS_PER_DAY - fractJD;
+    }
+
+    /* 21 is max width of (negative) wide-int (rather smaller, but anyway a time fraction below) */
+    if (FrmResultAllocate(dateFmt, 21) != TCL_OK) { return TCL_ERROR; };
+    dateFmt->output = _witoaw(dateFmt->output, intJD, '0', 1);
+    /* simplest cases .0 and .5 */
+    if (!fractJD || fractJD == (SECONDS_PER_DAY / 2)) {
+	/* point + 0 or 5 */
+	if (FrmResultAllocate(dateFmt, 1+1) != TCL_OK) { return TCL_ERROR; };
+	*dateFmt->output++ = '.';
+	*dateFmt->output++ = !fractJD ? '0' : '5';
+	*dateFmt->output = '\0';
+	return TCL_OK;
+    } else {
+	/* wrap the time fraction */
+	#define JDN_MAX_PRECISION 8
+	#define JDN_MAX_PRECBOUND 100000000 /* 10**JDN_MAX_PRECISION */
+	char *p;
+
+	/* to float (part after floating point, + 0.5 to round it up) */
+	fractJD = (int)(
+	    (double)fractJD * JDN_MAX_PRECBOUND / SECONDS_PER_DAY + 0.5
+	);
+	/* point + integer (as time fraction after floating point) */
+	if (FrmResultAllocate(dateFmt, 1+JDN_MAX_PRECISION) != TCL_OK) { return TCL_ERROR; };
+	*dateFmt->output++ = '.';
+	p = _itoaw(dateFmt->output, fractJD, '0', JDN_MAX_PRECISION);
+	/* remove trailing zero's */
+	dateFmt->output++;
+	while (p > dateFmt->output && *(p-1) == '0') {p--;}
+	*p = '\0';
+	dateFmt->output = p;
+    }
+    return TCL_OK;
+}
+static int
+ClockFmtToken_TimeZone_Proc(
+    ClockFmtScnCmdArgs *opts,
+    DateFormat *dateFmt,
+    ClockFormatToken *tok,
+    TCL_UNUSED(int *))
+{
+    if (*tok->tokWord.start == 'z') {
+	int z = dateFmt->date.tzOffset;
+	char sign = '+';
+
+	if ( z < 0 ) {
+	    z = -z;
+	    sign = '-';
+	}
+	if (FrmResultAllocate(dateFmt, 7) != TCL_OK) { return TCL_ERROR; };
+	*dateFmt->output++ = sign;
+	dateFmt->output = _itoaw(dateFmt->output, z / 3600, '0', 2);
+	z %= 3600;
+	dateFmt->output = _itoaw(dateFmt->output, z / 60, '0', 2);
+	z %= 60;
+	if (z != 0) {
+	    dateFmt->output = _itoaw(dateFmt->output, z, '0', 2);
+	}
+    } else {
+	Tcl_Obj * objPtr;
+	const char *s; Tcl_Size len;
+	/* convert seconds to local seconds to obtain tzName object */
+	if (ConvertUTCToLocal(opts->clientData, opts->interp,
+		&dateFmt->date, opts->timezoneObj,
+		GREGORIAN_CHANGE_DATE) != TCL_OK) {
+	    return TCL_ERROR;
+	};
+	objPtr = dateFmt->date.tzName;
+	s = TclGetStringFromObj(objPtr, &len);
+	if (FrmResultAllocate(dateFmt, len) != TCL_OK) { return TCL_ERROR; };
+	memcpy(dateFmt->output, s, len + 1);
+	dateFmt->output += len;
+    }
+    return TCL_OK;
+}
+
+static int
+ClockFmtToken_LocaleERA_Proc(
+    ClockFmtScnCmdArgs *opts,
+    DateFormat *dateFmt,
+    TCL_UNUSED(ClockFormatToken *),
+    TCL_UNUSED(int *))
+{
+    Tcl_Obj *mcObj;
+    const char *s;
+    Tcl_Size len;
+
+    if (dateFmt->date.isBce) {
+	mcObj = ClockMCGet(opts, MCLIT_BCE);
+    } else {
+	mcObj = ClockMCGet(opts, MCLIT_CE);
+    }
+    if (mcObj == NULL) {
+	return TCL_ERROR;
+    }
+    s = TclGetStringFromObj(mcObj, &len);
+    if (FrmResultAllocate(dateFmt, len) != TCL_OK) { return TCL_ERROR; };
+    memcpy(dateFmt->output, s, len + 1);
+    dateFmt->output += len;
+
+    return TCL_OK;
+}
+
+static int
+ClockFmtToken_LocaleERAYear_Proc(
+    ClockFmtScnCmdArgs *opts,
+    DateFormat *dateFmt,
+    ClockFormatToken *tok,
+    int *val)
+{
+    Tcl_Size rowc;
+    Tcl_Obj **rowv;
+
+    if (dateFmt->localeEra == NULL) {
+	Tcl_Obj *mcObj = ClockMCGet(opts, MCLIT_LOCALE_ERAS);
+	if (mcObj == NULL) {
+	    return TCL_ERROR;
+	}
+	if (TclListObjGetElements(opts->interp, mcObj, &rowc, &rowv) != TCL_OK) {
+	    return TCL_ERROR;
+	}
+	if (rowc != 0) {
+	    dateFmt->localeEra = LookupLastTransition(opts->interp,
+		dateFmt->date.localSeconds, rowc, rowv, NULL);
+	}
+	if (dateFmt->localeEra == NULL) {
+	    dateFmt->localeEra = (Tcl_Obj*)1;
+	}
+    }
+
+    /* if no LOCALE_ERAS in catalog or era not found */
+    if (dateFmt->localeEra == (Tcl_Obj*)1) {
+	if (FrmResultAllocate(dateFmt, 11) != TCL_OK) { return TCL_ERROR; };
+	if (*tok->tokWord.start == 'C') { /* %EC */
+	    *val = dateFmt->date.year / 100;
+	    dateFmt->output = _itoaw(dateFmt->output,
+		*val, '0', 2);
+	} else {			  /* %Ey */
+	    *val = dateFmt->date.year % 100;
+	    dateFmt->output = _itoaw(dateFmt->output,
+		*val, '0', 2);
+	}
+    } else {
+	Tcl_Obj *objPtr;
+	const char *s;
+	Tcl_Size len;
+	if (*tok->tokWord.start == 'C') { /* %EC */
+	    if (Tcl_ListObjIndex(opts->interp, dateFmt->localeEra, 1,
+			&objPtr) != TCL_OK ) {
+		return TCL_ERROR;
+	    }
+	} else {			  /* %Ey */
+	    if (Tcl_ListObjIndex(opts->interp, dateFmt->localeEra, 2,
+			&objPtr) != TCL_OK ) {
+		return TCL_ERROR;
+	    }
+	    if (Tcl_GetIntFromObj(opts->interp, objPtr, val) != TCL_OK) {
+		return TCL_ERROR;
+	    }
+	    *val = dateFmt->date.year - *val;
+	    /* if year in locale numerals */
+	    if (*val >= 0 && *val < 100) {
+		/* year as integer */
+		Tcl_Obj * mcObj = ClockMCGet(opts, MCLIT_LOCALE_NUMERALS);
+		if (mcObj == NULL) {
+		    return TCL_ERROR;
+		}
+		if (Tcl_ListObjIndex(opts->interp, mcObj, *val, &objPtr) != TCL_OK) {
+		    return TCL_ERROR;
+		}
+	    } else {
+		/* year as integer */
+		if (FrmResultAllocate(dateFmt, 11) != TCL_OK) { return TCL_ERROR; };
+		dateFmt->output = _itoaw(dateFmt->output,
+		    *val, '0', 2);
+		return TCL_OK;
+	    }
+	}
+	s = TclGetStringFromObj(objPtr, &len);
+	if (FrmResultAllocate(dateFmt, len) != TCL_OK) { return TCL_ERROR; };
+	memcpy(dateFmt->output, s, len + 1);
+	dateFmt->output += len;
+    }
+    return TCL_OK;
+}
+
+
+static const char *FmtSTokenMapIndex =
+    "demNbByYCHMSIklpaAuwUVzgGjJsntQ";
+static ClockFormatTokenMap FmtSTokenMap[] = {
+    /* %d */
+    {CTOKT_INT, "0", 2, 0, 0, 0, offsetof(DateFormat, date.dayOfMonth), NULL, NULL},
+    /* %e */
+    {CTOKT_INT, " ", 2, 0, 0, 0, offsetof(DateFormat, date.dayOfMonth), NULL, NULL},
+    /* %m */
+    {CTOKT_INT, "0", 2, 0, 0, 0, offsetof(DateFormat, date.month), NULL, NULL},
+    /* %N */
+    {CTOKT_INT, " ", 2, 0, 0, 0, offsetof(DateFormat, date.month), NULL, NULL},
+    /* %b %h */
+    {CTOKT_INT, NULL, 0, CLFMT_LOCALE_INDX | CLFMT_DECR, 0, 12, offsetof(DateFormat, date.month),
+	NULL, (void *)MCLIT_MONTHS_ABBREV},
+    /* %B */
+    {CTOKT_INT, NULL, 0, CLFMT_LOCALE_INDX | CLFMT_DECR, 0, 12, offsetof(DateFormat, date.month),
+	NULL, (void *)MCLIT_MONTHS_FULL},
+    /* %y */
+    {CTOKT_INT, "0", 2, 0, 0, 100, offsetof(DateFormat, date.year), NULL, NULL},
+    /* %Y */
+    {CTOKT_INT, "0", 4, 0, 0, 0, offsetof(DateFormat, date.year), NULL, NULL},
+    /* %C */
+    {CTOKT_INT, "0", 2, 0, 100, 0, offsetof(DateFormat, date.year), NULL, NULL},
+    /* %H */
+    {CTOKT_INT, "0", 2, 0, 3600, 24, offsetof(DateFormat, date.secondOfDay), NULL, NULL},
+    /* %M */
+    {CTOKT_INT, "0", 2, 0, 60, 60, offsetof(DateFormat, date.secondOfDay), NULL, NULL},
+    /* %S */
+    {CTOKT_INT, "0", 2, 0, 0, 60, offsetof(DateFormat, date.secondOfDay), NULL, NULL},
+    /* %I */
+    {CTOKT_INT, "0", 2, CLFMT_CALC, 0, 0, offsetof(DateFormat, date.secondOfDay),
+	ClockFmtToken_HourAMPM_Proc, NULL},
+    /* %k */
+    {CTOKT_INT, " ", 2, 0, 3600, 24, offsetof(DateFormat, date.secondOfDay), NULL, NULL},
+    /* %l */
+    {CTOKT_INT, " ", 2, CLFMT_CALC, 0, 0, offsetof(DateFormat, date.secondOfDay),
+	ClockFmtToken_HourAMPM_Proc, NULL},
+    /* %p %P */
+    {CTOKT_INT, NULL, 0, 0, 0, 0, offsetof(DateFormat, date.secondOfDay),
+	ClockFmtToken_AMPM_Proc, NULL},
+    /* %a */
+    {CTOKT_INT, NULL, 0, CLFMT_LOCALE_INDX, 0, 7, offsetof(DateFormat, date.dayOfWeek),
+	NULL, (void *)MCLIT_DAYS_OF_WEEK_ABBREV},
+    /* %A */
+    {CTOKT_INT, NULL, 0, CLFMT_LOCALE_INDX, 0, 7, offsetof(DateFormat, date.dayOfWeek),
+	NULL, (void *)MCLIT_DAYS_OF_WEEK_FULL},
+    /* %u */
+    {CTOKT_INT, " ", 1, 0, 0, 0, offsetof(DateFormat, date.dayOfWeek), NULL, NULL},
+    /* %w */
+    {CTOKT_INT, " ", 1, 0, 0, 7, offsetof(DateFormat, date.dayOfWeek), NULL, NULL},
+    /* %U %W */
+    {CTOKT_INT, "0", 2, CLFMT_CALC, 0, 0, offsetof(DateFormat, date.dayOfYear),
+	ClockFmtToken_WeekOfYear_Proc, NULL},
+    /* %V */
+    {CTOKT_INT, "0", 2, 0, 0, 0, offsetof(DateFormat, date.iso8601Week), NULL, NULL},
+    /* %z %Z */
+    {CFMTT_PROC, NULL, 0, 0, 0, 0, 0,
+	ClockFmtToken_TimeZone_Proc, NULL},
+    /* %g */
+    {CTOKT_INT, "0", 2, 0, 0, 100, offsetof(DateFormat, date.iso8601Year), NULL, NULL},
+    /* %G */
+    {CTOKT_INT, "0", 4, 0, 0, 0, offsetof(DateFormat, date.iso8601Year), NULL, NULL},
+    /* %j */
+    {CTOKT_INT, "0", 3, 0, 0, 0, offsetof(DateFormat, date.dayOfYear), NULL, NULL},
+    /* %J */
+    {CTOKT_WIDE, "0", 7, 0, 0, 0, offsetof(DateFormat, date.julianDay), NULL, NULL},
+    /* %s */
+    {CTOKT_WIDE, "0", 1, 0, 0, 0, offsetof(DateFormat, date.seconds), NULL, NULL},
+    /* %n */
+    {CTOKT_CHAR, "\n", 0, 0, 0, 0, 0, NULL, NULL},
+    /* %t */
+    {CTOKT_CHAR, "\t", 0, 0, 0, 0, 0, NULL, NULL},
+    /* %Q */
+    {CFMTT_PROC, NULL, 0, 0, 0, 0, 0,
+	ClockFmtToken_StarDate_Proc, NULL},
+};
+static const char *FmtSTokenMapAliasIndex[2] = {
+    "hPWZ",
+    "bpUz"
+};
+
+static const char *FmtETokenMapIndex =
+    "EJjys";
+static ClockFormatTokenMap FmtETokenMap[] = {
+    /* %EE */
+    {CFMTT_PROC, NULL, 0, 0, 0, 0, 0,
+	ClockFmtToken_LocaleERA_Proc, NULL},
+    /* %EJ */
+    {CFMTT_PROC, NULL, 0, 0, 0, 0, 0, /* calendar JDN starts at midnight */
+	ClockFmtToken_JDN_Proc, NULL},
+    /* %Ej */
+    {CFMTT_PROC, NULL, 0, 0, 0, 0, (SECONDS_PER_DAY/2), /* astro JDN starts at noon */
+	ClockFmtToken_JDN_Proc, NULL},
+    /* %Ey %EC */
+    {CTOKT_INT, NULL, 0, 0, 0, 0, offsetof(DateFormat, date.year),
+	ClockFmtToken_LocaleERAYear_Proc, NULL},
+    /* %Es */
+    {CTOKT_WIDE, "0", 1, 0, 0, 0, offsetof(DateFormat, date.localSeconds), NULL, NULL},
+};
+static const char *FmtETokenMapAliasIndex[2] = {
+    "C",
+    "y"
+};
+
+static const char *FmtOTokenMapIndex =
+    "dmyHIMSuw";
+static ClockFormatTokenMap FmtOTokenMap[] = {
+    /* %Od %Oe */
+    {CTOKT_INT, NULL, 0, CLFMT_LOCALE_INDX, 0, 100, offsetof(DateFormat, date.dayOfMonth),
+	NULL, (void *)MCLIT_LOCALE_NUMERALS},
+    /* %Om */
+    {CTOKT_INT, NULL, 0, CLFMT_LOCALE_INDX, 0, 100, offsetof(DateFormat, date.month),
+	NULL, (void *)MCLIT_LOCALE_NUMERALS},
+    /* %Oy */
+    {CTOKT_INT, NULL, 0, CLFMT_LOCALE_INDX, 0, 100, offsetof(DateFormat, date.year),
+	NULL, (void *)MCLIT_LOCALE_NUMERALS},
+    /* %OH %Ok */
+    {CTOKT_INT, NULL, 0, CLFMT_LOCALE_INDX, 3600, 24, offsetof(DateFormat, date.secondOfDay),
+	NULL, (void *)MCLIT_LOCALE_NUMERALS},
+    /* %OI %Ol */
+    {CTOKT_INT, NULL, 0, CLFMT_CALC | CLFMT_LOCALE_INDX, 0, 0, offsetof(DateFormat, date.secondOfDay),
+	ClockFmtToken_HourAMPM_Proc, (void *)MCLIT_LOCALE_NUMERALS},
+    /* %OM */
+    {CTOKT_INT, NULL, 0, CLFMT_LOCALE_INDX, 60, 60, offsetof(DateFormat, date.secondOfDay),
+	NULL, (void *)MCLIT_LOCALE_NUMERALS},
+    /* %OS */
+    {CTOKT_INT, NULL, 0, CLFMT_LOCALE_INDX, 0, 60, offsetof(DateFormat, date.secondOfDay),
+	NULL, (void *)MCLIT_LOCALE_NUMERALS},
+    /* %Ou */
+    {CTOKT_INT, NULL, 0, CLFMT_LOCALE_INDX, 0, 100, offsetof(DateFormat, date.dayOfWeek),
+	NULL, (void *)MCLIT_LOCALE_NUMERALS},
+    /* %Ow */
+    {CTOKT_INT, NULL, 0, CLFMT_LOCALE_INDX, 0, 7, offsetof(DateFormat, date.dayOfWeek),
+	NULL, (void *)MCLIT_LOCALE_NUMERALS},
+};
+static const char *FmtOTokenMapAliasIndex[2] = {
+    "ekl",
+    "dHI"
+};
+
+static ClockFormatTokenMap FmtWordTokenMap = {
+    CTOKT_WORD, NULL, 0, 0, 0, 0, 0, NULL, NULL
+};
+
+/*
+ *----------------------------------------------------------------------
+ */
+ClockFmtScnStorage *
+ClockGetOrParseFmtFormat(
+    Tcl_Interp *interp,		/* Tcl interpreter */
+    Tcl_Obj    *formatObj)	/* Format container */
+{
+    ClockFmtScnStorage *fss;
+
+    fss = Tcl_GetClockFrmScnFromObj(interp, formatObj);
+    if (fss == NULL) {
+	return NULL;
+    }
+
+    /* if format (fmtTok) already tokenized */
+    if (fss->fmtTok != NULL) {
+	return fss;
+    }
+
+    Tcl_MutexLock(&ClockFmtMutex);
+
+    /* first time formatting - tokenize format */
+    if (fss->fmtTok == NULL) {
+	ClockFormatToken *tok, *fmtTok;
+	unsigned int tokCnt;
+	const char *p, *e, *cp;
+
+	e = p = HashEntry4FmtScn(fss)->key.string;
+	e += strlen(p);
+
+	/* estimate token count by % char and format length */
+	fss->fmtTokC = EstimateTokenCount(p, e);
+
+	fmtTok = tok = (ClockFormatToken *)Tcl_Alloc(sizeof(*tok) * fss->fmtTokC);
+	memset(tok, 0, sizeof(*(tok)));
+	tokCnt = 1;
+	while (p < e) {
+	    switch (*p) {
+	    case '%':
+	    if (1) {
+		ClockFormatTokenMap * fmtMap = FmtSTokenMap;
+		const char *mapIndex =	FmtSTokenMapIndex,
+			  **aliasIndex = FmtSTokenMapAliasIndex;
+		if (p+1 >= e) {
+		    goto word_tok;
+		}
+		p++;
+		/* try to find modifier: */
+		switch (*p) {
+		case '%':
+		    /* begin new word token - don't join with previous word token,
+		     * because current mapping should be "...%%..." -> "...%..." */
+		    tok->map = &FmtWordTokenMap;
+		    tok->tokWord.start = p;
+		    tok->tokWord.end = p+1;
+		    AllocTokenInChain(tok, fmtTok, fss->fmtTokC, ClockFormatToken *); tokCnt++;
+		    p++;
+		    continue;
+		break;
+		case 'E':
+		    fmtMap = FmtETokenMap,
+		    mapIndex =	FmtETokenMapIndex,
+		    aliasIndex = FmtETokenMapAliasIndex;
+		    p++;
+		break;
+		case 'O':
+		    fmtMap = FmtOTokenMap,
+		    mapIndex = FmtOTokenMapIndex,
+		    aliasIndex = FmtOTokenMapAliasIndex;
+		    p++;
+		break;
+		}
+		/* search direct index */
+		cp = strchr(mapIndex, *p);
+		if (!cp || *cp == '\0') {
+		    /* search wrapper index (multiple chars for same token) */
+		    cp = strchr(aliasIndex[0], *p);
+		    if (!cp || *cp == '\0') {
+			p--; if (fmtMap != FmtSTokenMap) p--;
+			goto word_tok;
+		    }
+		    cp = strchr(mapIndex, aliasIndex[1][cp - aliasIndex[0]]);
+		    if (!cp || *cp == '\0') { /* unexpected, but ... */
+		    #ifdef DEBUG
+			Tcl_Panic("token \"%c\" has no map in wrapper resolver", *p);
+		    #endif
+			p--; if (fmtMap != FmtSTokenMap) p--;
+			goto word_tok;
+		    }
+		}
+		tok->map = &fmtMap[cp - mapIndex];
+		tok->tokWord.start = p;
+		/* next token */
+		AllocTokenInChain(tok, fmtTok, fss->fmtTokC, ClockFormatToken *); tokCnt++;
+		p++;
+		continue;
+	    }
+	    break;
+	    default:
+word_tok:
+	    if (1) {
+		ClockFormatToken *wordTok = tok;
+		if (tok > fmtTok && (tok-1)->map == &FmtWordTokenMap) {
+		    wordTok = tok-1;
+		}
+		if (wordTok == tok) {
+		    wordTok->tokWord.start = p;
+		    wordTok->map = &FmtWordTokenMap;
+		    AllocTokenInChain(tok, fmtTok, fss->fmtTokC, ClockFormatToken *); tokCnt++;
+		}
+		p = Tcl_UtfNext(p);
+		wordTok->tokWord.end = p;
+	    }
+	    break;
+	    }
+	}
+
+	/* correct count of real used tokens and free mem if desired
+	 * (1 is acceptable delta to prevent memory fragmentation) */
+	if (fss->fmtTokC > tokCnt + (CLOCK_MIN_TOK_CHAIN_BLOCK_SIZE / 2)) {
+	    if ( (tok = (ClockFormatToken *)Tcl_Realloc(fmtTok, tokCnt * sizeof(*tok))) != NULL ) {
+		fmtTok = tok;
+	    }
+	}
+
+	/* now we're ready - assign now to storage (note the threaded race condition) */
+	fss->fmtTok = fmtTok;
+	fss->fmtTokC = tokCnt;
+    }
+done:
+    Tcl_MutexUnlock(&ClockFmtMutex);
+
+    return fss;
+}
+
+/*
+ *----------------------------------------------------------------------
+ */
+int
+ClockFormat(
+    DateFormat *dateFmt, /* Date fields used for parsing & converting */
+    ClockFmtScnCmdArgs *opts)	  /* Command options */
+{
+    ClockFmtScnStorage	*fss;
+    ClockFormatToken	*tok;
+    ClockFormatTokenMap *map;
+    char resMem[MIN_FMT_RESULT_BLOCK_ALLOC];
+
+    /* get localized format */
+    if (ClockLocalizeFormat(opts) == NULL) {
+	return TCL_ERROR;
+    }
+
+    if ( !(fss = ClockGetOrParseFmtFormat(opts->interp, opts->formatObj))
+      || !(tok = fss->fmtTok)
+    ) {
+	return TCL_ERROR;
+    }
+
+    /* result container object */
+    dateFmt->resMem = resMem;
+    dateFmt->resEnd = dateFmt->resMem + sizeof(resMem);
+    if (fss->fmtMinAlloc > sizeof(resMem)) {
+	dateFmt->resMem = (char *)Tcl_Alloc(fss->fmtMinAlloc);
+	dateFmt->resEnd = dateFmt->resMem + fss->fmtMinAlloc;
+	if (dateFmt->resMem == NULL) {
+	    return TCL_ERROR;
+	}
+    }
+    dateFmt->output = dateFmt->resMem;
+    *dateFmt->output = '\0';
+
+    /* do format each token */
+    for (; tok->map != NULL; tok++) {
+	map = tok->map;
+	switch (map->type)
+	{
+	case CTOKT_INT:
+	if (1) {
+	    int val = (int)*(int *)(((char *)dateFmt) + map->offs);
+	    if (map->fmtproc == NULL) {
+		if (map->flags & CLFMT_DECR) {
+		    val--;
+		}
+		if (map->flags & CLFMT_INCR) {
+		    val++;
+		}
+		if (map->divider) {
+		    val /= map->divider;
+		}
+		if (map->divmod) {
+		    val %= map->divmod;
+		}
+	    } else {
+		if (map->fmtproc(opts, dateFmt, tok, &val) != TCL_OK) {
+		    goto done;
+		}
+		/* if not calculate only (output inside fmtproc) */
+		if (!(map->flags & CLFMT_CALC)) {
+		    continue;
+		}
+	    }
+	    if (!(map->flags & CLFMT_LOCALE_INDX)) {
+		if (FrmResultAllocate(dateFmt, 11) != TCL_OK) { goto error; };
+		if (map->width) {
+		    dateFmt->output = _itoaw(dateFmt->output, val, *map->tostr, map->width);
+		} else {
+		    dateFmt->output += sprintf(dateFmt->output, map->tostr, val);
+		}
+	    } else {
+		const char *s;
+		Tcl_Obj * mcObj = ClockMCGet(opts, PTR2INT(map->data) /* mcKey */);
+		if (mcObj == NULL) {
+		    goto error;
+		}
+		if ( Tcl_ListObjIndex(opts->interp, mcObj, val, &mcObj) != TCL_OK
+		  || mcObj == NULL
+		) {
+		    goto error;
+		}
+		s = TclGetString(mcObj);
+		if (FrmResultAllocate(dateFmt, mcObj->length) != TCL_OK) { goto error; };
+		memcpy(dateFmt->output, s, mcObj->length + 1);
+		dateFmt->output += mcObj->length;
+	    }
+	}
+	break;
+	case CTOKT_WIDE:
+	if (1) {
+	    Tcl_WideInt val = *(Tcl_WideInt *)(((char *)dateFmt) + map->offs);
+	    if (FrmResultAllocate(dateFmt, 21) != TCL_OK) { goto error; };
+	    if (map->width) {
+		dateFmt->output = _witoaw(dateFmt->output, val, *map->tostr, map->width);
+	    } else {
+		dateFmt->output += sprintf(dateFmt->output, map->tostr, val);
+	    }
+	}
+	break;
+	case CTOKT_CHAR:
+	    if (FrmResultAllocate(dateFmt, 1) != TCL_OK) { goto error; };
+	    *dateFmt->output++ = *map->tostr;
+	break;
+	case CFMTT_PROC:
+	    if (map->fmtproc(opts, dateFmt, tok, NULL) != TCL_OK) {
+		goto error;
+	    };
+	break;
+	case CTOKT_WORD:
+	    if (1) {
+		Tcl_Size len = tok->tokWord.end - tok->tokWord.start;
+		if (FrmResultAllocate(dateFmt, len) != TCL_OK) { goto error; };
+		if (len == 1) {
+		    *dateFmt->output++ = *tok->tokWord.start;
+		} else {
+		    memcpy(dateFmt->output, tok->tokWord.start, len);
+		    dateFmt->output += len;
+		}
+	    }
+	break;
+	}
+    }
+
+    goto done;
+
+error:
+
+    if (dateFmt->resMem != resMem) {
+	Tcl_Free(dateFmt->resMem);
+    }
+    dateFmt->resMem = NULL;
+
+done:
+
+    if (dateFmt->resMem) {
+	size_t size;
+	Tcl_Obj *result;
+	TclNewObj(result);
+	result->length = dateFmt->output - dateFmt->resMem;
+	size = result->length+1;
+	if (dateFmt->resMem == resMem) {
+	    result->bytes = (char *)Tcl_Alloc(size);
+	    if (result->bytes == NULL) {
+		return TCL_ERROR;
+	    }
+	    memcpy(result->bytes, dateFmt->resMem, size);
+	} else if ((dateFmt->resEnd - dateFmt->resMem) / size > MAX_FMT_RESULT_THRESHOLD) {
+	    result->bytes = (char *)Tcl_Realloc(dateFmt->resMem, size);
+	    if (result->bytes == NULL) {
+		result->bytes = dateFmt->resMem;
+	    }
+	} else {
+	    result->bytes = dateFmt->resMem;
+	}
+	/* save last used buffer length */
+	if ( dateFmt->resMem != resMem
+	  && fss->fmtMinAlloc < size + MIN_FMT_RESULT_BLOCK_DELTA
+	) {
+	    fss->fmtMinAlloc = size + MIN_FMT_RESULT_BLOCK_DELTA;
+	}
+	result->bytes[result->length] = '\0';
+	Tcl_SetObjResult(opts->interp, result);
+	return TCL_OK;
+    }
+
+    return TCL_ERROR;
+}
+
+
+void
+ClockFrmScnClearCaches(void)
+{
+    Tcl_MutexLock(&ClockFmtMutex);
+    /* clear caches ... */
+    Tcl_MutexUnlock(&ClockFmtMutex);
+}
+
+static void
+ClockFrmScnFinalize(
+    TCL_UNUSED(void *))
+{
+    Tcl_MutexLock(&ClockFmtMutex);
+#if CLOCK_FMT_SCN_STORAGE_GC_SIZE > 0
+    /* clear GC */
+    ClockFmtScnStorage_GC.stackPtr = NULL;
+    ClockFmtScnStorage_GC.stackBound = NULL;
+    ClockFmtScnStorage_GC.count = 0;
+#endif
+    if (initialized) {
+	Tcl_DeleteHashTable(&FmtScnHashTable);
+	initialized = 0;
+    }
+    Tcl_MutexUnlock(&ClockFmtMutex);
+    Tcl_MutexFinalize(&ClockFmtMutex);
+}
+/*
+ * Local Variables:
+ * mode: c
+ * c-basic-offset: 4
+ * fill-column: 78
+ * End:
+ */
diff --git a/generic/tclDate.c b/generic/tclDate.c
index 8c048a6..e419585 100644
--- a/generic/tclDate.c
+++ b/generic/tclDate.c
@@ -78,8 +78,9 @@
  *	This file is generated from a yacc grammar defined in the file
  *	tclGetDate.y. It should not be edited directly.
  *
- * Copyright (c) 1992-1995 Karl Lehenbauer & Mark Diekhans.
- * Copyright (c) 1995-1997 Sun Microsystems, Inc.
+ * Copyright © 1992-1995 Karl Lehenbauer & Mark Diekhans.
+ * Copyright © 1995-1997 Sun Microsystems, Inc.
+ * Copyright © 2015 Sergey G. Brester aka sebres.
  *
  * See the file "license.terms" for information on usage and redistribution of
  * this file, and for a DISCLAIMER OF ALL WARRANTIES.
@@ -96,86 +97,20 @@
 #pragma warning( disable : 4102 )
 #endif /* _MSC_VER */
 
-/*
- * Meridian: am, pm, or 24-hour style.
- */
-
-typedef enum _MERIDIAN {
-    MERam, MERpm, MER24
-} MERIDIAN;
+#if 0
+#define YYDEBUG 1
+#endif
 
 /*
  * yyparse will accept a 'struct DateInfo' as its parameter; that's where the
  * parsed fields will be returned.
  */
 
-typedef struct DateInfo {
-
-    Tcl_Obj* messages;		/* Error messages */
-    const char* separatrix;	/* String separating messages */
-
-    time_t dateYear;
-    time_t dateMonth;
-    time_t dateDay;
-    int dateHaveDate;
-
-    time_t dateHour;
-    time_t dateMinutes;
-    time_t dateSeconds;
-    MERIDIAN dateMeridian;
-    int dateHaveTime;
-
-    time_t dateTimezone;
-    int dateDSTmode;
-    int dateHaveZone;
-
-    time_t dateRelMonth;
-    time_t dateRelDay;
-    time_t dateRelSeconds;
-    int dateHaveRel;
-
-    time_t dateMonthOrdinal;
-    int dateHaveOrdinalMonth;
-
-    time_t dateDayOrdinal;
-    time_t dateDayNumber;
-    int dateHaveDay;
-
-    const char *dateStart;
-    const char *dateInput;
-    time_t *dateRelPointer;
-
-    int dateDigitCount;
-} DateInfo;
+#include "tclDate.h"
 
 #define YYMALLOC	Tcl_Alloc
 #define YYFREE(x)	(Tcl_Free((void*) (x)))
 
-#define yyDSTmode	(info->dateDSTmode)
-#define yyDayOrdinal	(info->dateDayOrdinal)
-#define yyDayNumber	(info->dateDayNumber)
-#define yyMonthOrdinal	(info->dateMonthOrdinal)
-#define yyHaveDate	(info->dateHaveDate)
-#define yyHaveDay	(info->dateHaveDay)
-#define yyHaveOrdinalMonth (info->dateHaveOrdinalMonth)
-#define yyHaveRel	(info->dateHaveRel)
-#define yyHaveTime	(info->dateHaveTime)
-#define yyHaveZone	(info->dateHaveZone)
-#define yyTimezone	(info->dateTimezone)
-#define yyDay		(info->dateDay)
-#define yyMonth		(info->dateMonth)
-#define yyYear		(info->dateYear)
-#define yyHour		(info->dateHour)
-#define yyMinutes	(info->dateMinutes)
-#define yySeconds	(info->dateSeconds)
-#define yyMeridian	(info->dateMeridian)
-#define yyRelMonth	(info->dateRelMonth)
-#define yyRelDay	(info->dateRelDay)
-#define yyRelSeconds	(info->dateRelSeconds)
-#define yyRelPointer	(info->dateRelPointer)
-#define yyInput		(info->dateInput)
-#define yyDigitCount	(info->dateDigitCount)
-
 #define EPOCH		1970
 #define START_OF_TIME	1902
 #define END_OF_TIME	2037
@@ -187,18 +122,24 @@ typedef struct DateInfo {
 
 #define TM_YEAR_BASE	1900
 
-#define HOUR(x)		((int) (60 * (x)))
-#define SECSPERDAY	(24L * 60L * 60L)
+#define HOUR(x)		((60 * (int)(x)))
 #define IsLeapYear(x)	(((x) % 4 == 0) && ((x) % 100 != 0 || (x) % 400 == 0))
 
+#define yyIncrFlags(f)				\
+    do {					\
+	info->errFlags |= (info->flags & (f));	\
+	if (info->errFlags) { YYABORT; }	\
+	info->flags |= (f);			\
+    } while (0);
+
 /*
  * An entry in the lexical lookup table.
  */
 
-typedef struct _TABLE {
+typedef struct {
     const char *name;
     int type;
-    time_t value;
+    int value;
 } TABLE;
 
 /*
@@ -259,14 +200,18 @@ extern int TclDatedebug;
     tMONTH_UNIT = 264,             /* tMONTH_UNIT  */
     tSTARDATE = 265,               /* tSTARDATE  */
     tSEC_UNIT = 266,               /* tSEC_UNIT  */
-    tSNUMBER = 267,                /* tSNUMBER  */
-    tUNUMBER = 268,                /* tUNUMBER  */
-    tZONE = 269,                   /* tZONE  */
-    tEPOCH = 270,                  /* tEPOCH  */
-    tDST = 271,                    /* tDST  */
-    tISOBASE = 272,                /* tISOBASE  */
-    tDAY_UNIT = 273,               /* tDAY_UNIT  */
-    tNEXT = 274                    /* tNEXT  */
+    tUNUMBER = 267,                /* tUNUMBER  */
+    tZONE = 268,                   /* tZONE  */
+    tZONEwO4 = 269,                /* tZONEwO4  */
+    tZONEwO2 = 270,                /* tZONEwO2  */
+    tEPOCH = 271,                  /* tEPOCH  */
+    tDST = 272,                    /* tDST  */
+    tISOBAS8 = 273,                /* tISOBAS8  */
+    tISOBAS6 = 274,                /* tISOBAS6  */
+    tISOBASL = 275,                /* tISOBASL  */
+    tDAY_UNIT = 276,               /* tDAY_UNIT  */
+    tNEXT = 277,                   /* tNEXT  */
+    SP = 278                       /* SP  */
   };
   typedef enum yytokentype yytoken_kind_t;
 #endif
@@ -276,7 +221,7 @@ extern int TclDatedebug;
 union YYSTYPE
 {
 
-    time_t Number;
+    long long Number;
     enum _MERIDIAN Meridian;
 
 
@@ -323,36 +268,48 @@ enum yysymbol_kind_t
   YYSYMBOL_tMONTH_UNIT = 9,                /* tMONTH_UNIT  */
   YYSYMBOL_tSTARDATE = 10,                 /* tSTARDATE  */
   YYSYMBOL_tSEC_UNIT = 11,                 /* tSEC_UNIT  */
-  YYSYMBOL_tSNUMBER = 12,                  /* tSNUMBER  */
-  YYSYMBOL_tUNUMBER = 13,                  /* tUNUMBER  */
-  YYSYMBOL_tZONE = 14,                     /* tZONE  */
-  YYSYMBOL_tEPOCH = 15,                    /* tEPOCH  */
-  YYSYMBOL_tDST = 16,                      /* tDST  */
-  YYSYMBOL_tISOBASE = 17,                  /* tISOBASE  */
-  YYSYMBOL_tDAY_UNIT = 18,                 /* tDAY_UNIT  */
-  YYSYMBOL_tNEXT = 19,                     /* tNEXT  */
-  YYSYMBOL_20_ = 20,                       /* ':'  */
-  YYSYMBOL_21_ = 21,                       /* ','  */
-  YYSYMBOL_22_ = 22,                       /* '/'  */
-  YYSYMBOL_23_ = 23,                       /* '-'  */
-  YYSYMBOL_24_ = 24,                       /* '.'  */
-  YYSYMBOL_25_ = 25,                       /* '+'  */
-  YYSYMBOL_YYACCEPT = 26,                  /* $accept  */
-  YYSYMBOL_spec = 27,                      /* spec  */
-  YYSYMBOL_item = 28,                      /* item  */
-  YYSYMBOL_time = 29,                      /* time  */
-  YYSYMBOL_zone = 30,                      /* zone  */
-  YYSYMBOL_day = 31,                       /* day  */
-  YYSYMBOL_date = 32,                      /* date  */
-  YYSYMBOL_ordMonth = 33,                  /* ordMonth  */
-  YYSYMBOL_iso = 34,                       /* iso  */
-  YYSYMBOL_trek = 35,                      /* trek  */
-  YYSYMBOL_relspec = 36,                   /* relspec  */
-  YYSYMBOL_relunits = 37,                  /* relunits  */
-  YYSYMBOL_sign = 38,                      /* sign  */
-  YYSYMBOL_unit = 39,                      /* unit  */
-  YYSYMBOL_number = 40,                    /* number  */
-  YYSYMBOL_o_merid = 41                    /* o_merid  */
+  YYSYMBOL_tUNUMBER = 12,                  /* tUNUMBER  */
+  YYSYMBOL_tZONE = 13,                     /* tZONE  */
+  YYSYMBOL_tZONEwO4 = 14,                  /* tZONEwO4  */
+  YYSYMBOL_tZONEwO2 = 15,                  /* tZONEwO2  */
+  YYSYMBOL_tEPOCH = 16,                    /* tEPOCH  */
+  YYSYMBOL_tDST = 17,                      /* tDST  */
+  YYSYMBOL_tISOBAS8 = 18,                  /* tISOBAS8  */
+  YYSYMBOL_tISOBAS6 = 19,                  /* tISOBAS6  */
+  YYSYMBOL_tISOBASL = 20,                  /* tISOBASL  */
+  YYSYMBOL_tDAY_UNIT = 21,                 /* tDAY_UNIT  */
+  YYSYMBOL_tNEXT = 22,                     /* tNEXT  */
+  YYSYMBOL_SP = 23,                        /* SP  */
+  YYSYMBOL_24_ = 24,                       /* ':'  */
+  YYSYMBOL_25_ = 25,                       /* ','  */
+  YYSYMBOL_26_ = 26,                       /* '-'  */
+  YYSYMBOL_27_ = 27,                       /* '/'  */
+  YYSYMBOL_28_T_ = 28,                     /* 'T'  */
+  YYSYMBOL_29_ = 29,                       /* '.'  */
+  YYSYMBOL_30_ = 30,                       /* '+'  */
+  YYSYMBOL_YYACCEPT = 31,                  /* $accept  */
+  YYSYMBOL_spec = 32,                      /* spec  */
+  YYSYMBOL_item = 33,                      /* item  */
+  YYSYMBOL_iextime = 34,                   /* iextime  */
+  YYSYMBOL_time = 35,                      /* time  */
+  YYSYMBOL_zone = 36,                      /* zone  */
+  YYSYMBOL_comma = 37,                     /* comma  */
+  YYSYMBOL_day = 38,                       /* day  */
+  YYSYMBOL_iexdate = 39,                   /* iexdate  */
+  YYSYMBOL_date = 40,                      /* date  */
+  YYSYMBOL_ordMonth = 41,                  /* ordMonth  */
+  YYSYMBOL_isosep = 42,                    /* isosep  */
+  YYSYMBOL_isodate = 43,                   /* isodate  */
+  YYSYMBOL_isotime = 44,                   /* isotime  */
+  YYSYMBOL_iso = 45,                       /* iso  */
+  YYSYMBOL_trek = 46,                      /* trek  */
+  YYSYMBOL_relspec = 47,                   /* relspec  */
+  YYSYMBOL_relunits = 48,                  /* relunits  */
+  YYSYMBOL_sign = 49,                      /* sign  */
+  YYSYMBOL_unit = 50,                      /* unit  */
+  YYSYMBOL_INTNUM = 51,                    /* INTNUM  */
+  YYSYMBOL_numitem = 52,                   /* numitem  */
+  YYSYMBOL_o_merid = 53                    /* o_merid  */
 };
 typedef enum yysymbol_kind_t yysymbol_kind_t;
 
@@ -365,12 +322,10 @@ typedef enum yysymbol_kind_t yysymbol_kind_t;
  */
 
 static int		LookupWord(YYSTYPE* yylvalPtr, char *buff);
- static void		TclDateerror(YYLTYPE* location,
+static void		TclDateerror(YYLTYPE* location,
 				     DateInfo* info, const char *s);
- static int		TclDatelex(YYSTYPE* yylvalPtr, YYLTYPE* location,
+static int		TclDatelex(YYSTYPE* yylvalPtr, YYLTYPE* location,
 				   DateInfo* info);
-static time_t		ToSeconds(time_t Hours, time_t Minutes,
-			    time_t Seconds, MERIDIAN Meridian);
 MODULE_SCOPE int	yyparse(DateInfo*);
 
 
@@ -700,19 +655,19 @@ union yyalloc
 /* YYFINAL -- State number of the termination state.  */
 #define YYFINAL  2
 /* YYLAST -- Last index in YYTABLE.  */
-#define YYLAST   81
+#define YYLAST   98
 
 /* YYNTOKENS -- Number of terminals.  */
-#define YYNTOKENS  26
+#define YYNTOKENS  31
 /* YYNNTS -- Number of nonterminals.  */
-#define YYNNTS  16
+#define YYNNTS  23
 /* YYNRULES -- Number of rules.  */
-#define YYNRULES  56
+#define YYNRULES  72
 /* YYNSTATES -- Number of states.  */
-#define YYNSTATES  85
+#define YYNSTATES  103
 
 /* YYMAXUTOK -- Last valid token kind.  */
-#define YYMAXUTOK   274
+#define YYMAXUTOK   278
 
 
 /* YYTRANSLATE(TOKEN-NUM) -- Symbol number corresponding to TOKEN-NUM
@@ -730,11 +685,11 @@ static const yytype_int8 yytranslate[] =
        2,     2,     2,     2,     2,     2,     2,     2,     2,     2,
        2,     2,     2,     2,     2,     2,     2,     2,     2,     2,
        2,     2,     2,     2,     2,     2,     2,     2,     2,     2,
-       2,     2,     2,    25,    21,    23,    24,    22,     2,     2,
-       2,     2,     2,     2,     2,     2,     2,     2,    20,     2,
-       2,     2,     2,     2,     2,     2,     2,     2,     2,     2,
+       2,     2,     2,    30,    25,    26,    29,    27,     2,     2,
+       2,     2,     2,     2,     2,     2,     2,     2,    24,     2,
        2,     2,     2,     2,     2,     2,     2,     2,     2,     2,
        2,     2,     2,     2,     2,     2,     2,     2,     2,     2,
+       2,     2,     2,     2,    28,     2,     2,     2,     2,     2,
        2,     2,     2,     2,     2,     2,     2,     2,     2,     2,
        2,     2,     2,     2,     2,     2,     2,     2,     2,     2,
        2,     2,     2,     2,     2,     2,     2,     2,     2,     2,
@@ -753,19 +708,21 @@ static const yytype_int8 yytranslate[] =
        2,     2,     2,     2,     2,     2,     2,     2,     2,     2,
        2,     2,     2,     2,     2,     2,     1,     2,     3,     4,
        5,     6,     7,     8,     9,    10,    11,    12,    13,    14,
-      15,    16,    17,    18,    19
+      15,    16,    17,    18,    19,    20,    21,    22,    23
 };
 
 #if YYDEBUG
 /* YYRLINE[YYN] -- Source line where rule number YYN was defined.  */
 static const yytype_int16 yyrline[] =
 {
-       0,   223,   223,   224,   227,   230,   233,   236,   239,   242,
-     245,   249,   254,   257,   263,   269,   277,   282,   287,   291,
-     297,   301,   305,   309,   313,   319,   323,   328,   333,   338,
-     343,   347,   352,   356,   361,   368,   372,   378,   388,   397,
-     406,   416,   430,   435,   438,   441,   444,   447,   450,   455,
-     458,   463,   467,   471,   477,   495,   498
+       0,   171,   171,   172,   176,   179,   182,   185,   188,   191,
+     194,   197,   201,   204,   209,   215,   221,   226,   230,   234,
+     238,   242,   246,   252,   253,   256,   260,   264,   268,   272,
+     276,   282,   288,   292,   297,   298,   303,   307,   312,   316,
+     321,   328,   332,   338,   338,   340,   345,   350,   352,   357,
+     359,   360,   368,   379,   393,   398,   401,   404,   407,   410,
+     413,   416,   421,   424,   429,   433,   437,   443,   446,   449,
+     454,   472,   475
 };
 #endif
 
@@ -783,11 +740,12 @@ static const char *const yytname[] =
 {
   "\"end of file\"", "error", "\"invalid token\"", "tAGO", "tDAY",
   "tDAYZONE", "tID", "tMERIDIAN", "tMONTH", "tMONTH_UNIT", "tSTARDATE",
-  "tSEC_UNIT", "tSNUMBER", "tUNUMBER", "tZONE", "tEPOCH", "tDST",
-  "tISOBASE", "tDAY_UNIT", "tNEXT", "':'", "','", "'/'", "'-'", "'.'",
-  "'+'", "$accept", "spec", "item", "time", "zone", "day", "date",
-  "ordMonth", "iso", "trek", "relspec", "relunits", "sign", "unit",
-  "number", "o_merid", YY_NULLPTR
+  "tSEC_UNIT", "tUNUMBER", "tZONE", "tZONEwO4", "tZONEwO2", "tEPOCH",
+  "tDST", "tISOBAS8", "tISOBAS6", "tISOBASL", "tDAY_UNIT", "tNEXT", "SP",
+  "':'", "','", "'-'", "'/'", "'T'", "'.'", "'+'", "$accept", "spec",
+  "item", "iextime", "time", "zone", "comma", "day", "iexdate", "date",
+  "ordMonth", "isosep", "isodate", "isotime", "iso", "trek", "relspec",
+  "relunits", "sign", "unit", "INTNUM", "numitem", "o_merid", YY_NULLPTR
 };
 
 static const char *
@@ -797,12 +755,12 @@ yysymbol_name (yysymbol_kind_t yysymbol)
 }
 #endif
 
-#define YYPACT_NINF (-18)
+#define YYPACT_NINF (-21)
 
 #define yypact_value_is_default(Yyn) \
   ((Yyn) == YYPACT_NINF)
 
-#define YYTABLE_NINF (-1)
+#define YYTABLE_NINF (-68)
 
 #define yytable_value_is_error(Yyn) \
   0
@@ -811,15 +769,17 @@ yysymbol_name (yysymbol_kind_t yysymbol)
    STATE-NUM.  */
 static const yytype_int8 yypact[] =
 {
-     -18,     2,   -18,   -17,   -18,    -4,   -18,    10,   -18,    22,
-       8,   -18,    18,   -18,    39,   -18,   -18,   -18,   -18,   -18,
-     -18,   -18,   -18,   -18,   -18,   -18,    25,    21,   -18,   -18,
-     -18,    16,    14,   -18,   -18,    28,    36,    41,    -5,   -18,
-     -18,     5,   -18,   -18,   -18,    47,   -18,   -18,    42,    46,
-      48,   -18,    -6,    40,    43,    44,    49,   -18,   -18,   -18,
-     -18,   -18,   -18,   -18,   -18,    50,   -18,    51,    55,    57,
-      58,    65,   -18,   -18,    59,    54,   -18,    62,    63,    60,
-     -18,    64,    61,    66,   -18
+     -21,    11,   -21,   -20,   -21,     5,   -21,    -9,   -21,    46,
+      17,     9,     9,   -21,   -21,   -21,    24,   -21,    57,   -21,
+     -21,   -21,    33,   -21,   -21,   -21,   -21,   -21,   -21,   -15,
+     -21,   -21,   -21,    45,    26,   -21,    -7,   -21,    51,   -21,
+     -20,   -21,   -21,   -21,    48,   -21,   -21,    67,    68,    52,
+      69,   -21,    -9,    -9,   -21,   -21,   -21,   -21,    74,   -21,
+      -7,   -21,   -21,   -21,   -21,    44,   -21,    79,    40,    -7,
+     -21,   -21,    72,    73,   -21,    62,    61,    63,    64,   -21,
+     -21,   -21,   -21,    66,   -21,   -21,   -21,   -21,    84,    -7,
+     -21,   -21,   -21,    80,    81,    82,    83,   -21,   -21,   -21,
+     -21,   -21,   -21
 };
 
 /* YYDEFACT[STATE-NUM] -- Default reduction number in state STATE-NUM.
@@ -827,29 +787,33 @@ static const yytype_int8 yypact[] =
    means the default is an error.  */
 static const yytype_int8 yydefact[] =
 {
-       2,     0,     1,    20,    18,     0,    53,     0,    51,    54,
-      17,    33,    27,    52,     0,    49,    50,     3,     4,     5,
-       8,     6,     7,    10,    11,     9,    43,     0,    48,    12,
-      21,    30,     0,    22,    13,    32,     0,     0,     0,    45,
-      16,     0,    40,    24,    35,     0,    46,    42,    19,     0,
-       0,    34,    55,    25,     0,     0,     0,    38,    36,    47,
-      23,    44,    31,    41,    56,     0,    14,     0,     0,     0,
-       0,    55,    26,    28,    29,     0,    15,     0,     0,     0,
-      39,     0,     0,     0,    37
+       2,     0,     1,    25,    19,     0,    66,     0,    64,    70,
+      18,     0,     0,    39,    45,    46,     0,    65,     0,    62,
+      63,     3,    71,     4,     5,     8,    47,     6,     7,    34,
+      10,    11,     9,    55,     0,    61,     0,    12,    23,    26,
+      36,    67,    69,    68,     0,    27,    15,    38,     0,     0,
+       0,    17,     0,     0,    52,    51,    30,    41,    67,    59,
+       0,    72,    16,    44,    43,     0,    54,    67,     0,    22,
+      58,    24,     0,     0,    40,    14,     0,     0,    32,    20,
+      21,    42,    60,     0,    48,    49,    50,    29,    67,     0,
+      57,    37,    53,     0,     0,     0,     0,    28,    56,    13,
+      35,    31,    33
 };
 
 /* YYPGOTO[NTERM-NUM].  */
 static const yytype_int8 yypgoto[] =
 {
-     -18,   -18,   -18,   -18,   -18,   -18,   -18,   -18,   -18,   -18,
-     -18,   -18,   -18,    -9,   -18,     7
+     -21,   -21,   -21,    31,   -21,   -21,    58,   -21,   -21,   -21,
+     -21,   -21,   -21,   -21,   -21,   -21,   -21,   -21,    -5,   -18,
+      -6,   -21,   -21
 };
 
 /* YYDEFGOTO[NTERM-NUM].  */
 static const yytype_int8 yydefgoto[] =
 {
-       0,     1,    17,    18,    19,    20,    21,    22,    23,    24,
-      25,    26,    27,    28,    29,    66
+       0,     1,    21,    22,    23,    24,    39,    25,    26,    27,
+      28,    65,    29,    86,    30,    31,    32,    33,    34,    35,
+      36,    37,    62
 };
 
 /* YYTABLE[YYPACT[STATE-NUM]] -- What to do in state STATE-NUM.  If
@@ -857,65 +821,73 @@ static const yytype_int8 yydefgoto[] =
    number is the opposite.  If YYTABLE_NINF, syntax error.  */
 static const yytype_int8 yytable[] =
 {
-      39,    64,     2,    54,    30,    46,     3,     4,    55,    31,
-       5,     6,     7,     8,    65,     9,    10,    11,    56,    12,
-      13,    14,    57,    32,    40,    15,    33,    16,    47,    34,
-      35,     6,    41,     8,    48,    42,    59,    49,    50,    61,
-      13,    51,    36,    43,    37,    38,    60,    44,     6,    52,
-       8,     6,    45,     8,    53,    58,     6,    13,     8,    62,
-      13,    63,    67,    71,    72,    13,    68,    69,    73,    70,
-      74,    75,    64,    77,    78,    79,    80,    82,    76,    84,
-      81,    83
+      59,    44,     6,    41,     8,    38,    52,    53,    63,    42,
+      43,     2,    60,    64,    17,     3,     4,    40,    70,     5,
+       6,     7,     8,     9,    10,    11,    12,    13,    69,    14,
+      15,    16,    17,    18,    51,    19,    54,    19,    67,    20,
+      61,    20,    82,    55,    42,    43,    79,    80,    66,    68,
+      45,    90,    88,    46,    47,   -67,    83,   -67,    42,    43,
+      76,    56,    89,    84,    77,    57,     6,   -67,     8,    58,
+      48,    98,    49,    50,    71,    42,    43,    73,    17,    74,
+      75,    78,    81,    87,    91,    92,    93,    94,    97,    95,
+      48,    96,    99,   100,   101,   102,    85,     0,    72
 };
 
 static const yytype_int8 yycheck[] =
 {
-       9,     7,     0,     8,    21,    14,     4,     5,    13,    13,
-       8,     9,    10,    11,    20,    13,    14,    15,    13,    17,
-      18,    19,    17,    13,    16,    23,     4,    25,     3,     7,
-       8,     9,    14,    11,    13,    17,    45,    21,    24,    48,
-      18,    13,    20,     4,    22,    23,     4,     8,     9,    13,
-      11,     9,    13,    11,    13,     8,     9,    18,    11,    13,
-      18,    13,    22,    13,    13,    18,    23,    23,    13,    20,
-      13,    13,     7,    14,    20,    13,    13,    13,    71,    13,
-      20,    20
+      18,     7,     9,    12,    11,    25,    11,    12,    23,    18,
+      19,     0,    18,    28,    21,     4,     5,    12,    36,     8,
+       9,    10,    11,    12,    13,    14,    15,    16,    34,    18,
+      19,    20,    21,    22,    17,    26,    12,    26,    12,    30,
+       7,    30,    60,    19,    18,    19,    52,    53,     3,    23,
+       4,    69,    12,     7,     8,     9,    12,    11,    18,    19,
+       8,     4,    68,    19,    12,     8,     9,    21,    11,    12,
+      24,    89,    26,    27,    23,    18,    19,    29,    21,    12,
+      12,    12,     8,     4,    12,    12,    24,    26,     4,    26,
+      24,    27,    12,    12,    12,    12,    65,    -1,    40
 };
 
 /* YYSTOS[STATE-NUM] -- The symbol kind of the accessing symbol of
    state STATE-NUM.  */
 static const yytype_int8 yystos[] =
 {
-       0,    27,     0,     4,     5,     8,     9,    10,    11,    13,
-      14,    15,    17,    18,    19,    23,    25,    28,    29,    30,
-      31,    32,    33,    34,    35,    36,    37,    38,    39,    40,
-      21,    13,    13,     4,     7,     8,    20,    22,    23,    39,
-      16,    14,    17,     4,     8,    13,    39,     3,    13,    21,
-      24,    13,    13,    13,     8,    13,    13,    17,     8,    39,
-       4,    39,    13,    13,     7,    20,    41,    22,    23,    23,
-      20,    13,    13,    13,    13,    13,    41,    14,    20,    13,
-      13,    20,    13,    20,    13
+       0,    32,     0,     4,     5,     8,     9,    10,    11,    12,
+      13,    14,    15,    16,    18,    19,    20,    21,    22,    26,
+      30,    33,    34,    35,    36,    38,    39,    40,    41,    43,
+      45,    46,    47,    48,    49,    50,    51,    52,    25,    37,
+      12,    12,    18,    19,    51,     4,     7,     8,    24,    26,
+      27,    17,    49,    49,    12,    19,     4,     8,    12,    50,
+      51,     7,    53,    23,    28,    42,     3,    12,    23,    51,
+      50,    23,    37,    29,    12,    12,     8,    12,    12,    51,
+      51,     8,    50,    12,    19,    34,    44,     4,    12,    51,
+      50,    12,    12,    24,    26,    26,    27,     4,    50,    12,
+      12,    12,    12
 };
 
 /* YYR1[RULE-NUM] -- Symbol kind of the left-hand side of rule RULE-NUM.  */
 static const yytype_int8 yyr1[] =
 {
-       0,    26,    27,    27,    28,    28,    28,    28,    28,    28,
-      28,    28,    28,    29,    29,    29,    30,    30,    30,    30,
-      31,    31,    31,    31,    31,    32,    32,    32,    32,    32,
-      32,    32,    32,    32,    32,    33,    33,    34,    34,    34,
-      34,    35,    36,    36,    37,    37,    37,    37,    37,    38,
-      38,    39,    39,    39,    40,    41,    41
+       0,    31,    32,    32,    33,    33,    33,    33,    33,    33,
+      33,    33,    33,    34,    34,    35,    35,    36,    36,    36,
+      36,    36,    36,    37,    37,    38,    38,    38,    38,    38,
+      38,    39,    40,    40,    40,    40,    40,    40,    40,    40,
+      40,    41,    41,    42,    42,    43,    43,    43,    44,    44,
+      45,    45,    45,    46,    47,    47,    48,    48,    48,    48,
+      48,    48,    49,    49,    50,    50,    50,    51,    51,    51,
+      52,    53,    53
 };
 
 /* YYR2[RULE-NUM] -- Number of symbols on the right-hand side of rule RULE-NUM.  */
 static const yytype_int8 yyr2[] =
 {
        0,     2,     0,     2,     1,     1,     1,     1,     1,     1,
-       1,     1,     1,     2,     4,     6,     2,     1,     1,     2,
-       1,     2,     2,     3,     2,     3,     5,     1,     5,     5,
-       2,     4,     2,     1,     3,     2,     3,    11,     3,     7,
-       2,     4,     2,     1,     3,     2,     2,     3,     1,     1,
-       1,     1,     1,     1,     1,     0,     1
+       1,     1,     1,     5,     3,     2,     2,     2,     1,     1,
+       3,     3,     2,     1,     2,     1,     2,     2,     4,     3,
+       2,     5,     3,     5,     1,     5,     2,     4,     2,     1,
+       3,     2,     3,     1,     1,     1,     1,     1,     1,     1,
+       3,     2,     2,     4,     2,     1,     4,     3,     2,     2,
+       3,     1,     1,     1,     1,     1,     1,     1,     1,     1,
+       1,     0,     1
 };
 
 
@@ -1500,155 +1472,184 @@ yyreduce:
     {
   case 4: /* item: time  */
                {
-	    yyHaveTime++;
+	    yyIncrFlags(CLF_TIME);
 	}
     break;
 
   case 5: /* item: zone  */
                {
-	    yyHaveZone++;
+	    yyIncrFlags(CLF_ZONE);
 	}
     break;
 
   case 6: /* item: date  */
                {
-	    yyHaveDate++;
+	    yyIncrFlags(CLF_HAVEDATE);
 	}
     break;
 
   case 7: /* item: ordMonth  */
                    {
-	    yyHaveOrdinalMonth++;
+	    yyIncrFlags(CLF_ORDINALMONTH);
 	}
     break;
 
   case 8: /* item: day  */
               {
-	    yyHaveDay++;
+	    yyIncrFlags(CLF_DAYOFWEEK);
 	}
     break;
 
   case 9: /* item: relspec  */
                   {
-	    yyHaveRel++;
+	    info->flags |= CLF_RELCONV;
 	}
     break;
 
   case 10: /* item: iso  */
               {
-	    yyHaveTime++;
-	    yyHaveDate++;
+	    yyIncrFlags(CLF_TIME|CLF_HAVEDATE);
 	}
     break;
 
   case 11: /* item: trek  */
                {
-	    yyHaveTime++;
-	    yyHaveDate++;
-	    yyHaveRel++;
+	    yyIncrFlags(CLF_TIME|CLF_HAVEDATE);
+	    info->flags |= CLF_RELCONV;
 	}
     break;
 
-  case 13: /* time: tUNUMBER tMERIDIAN  */
-                             {
-	    yyHour = (yyvsp[-1].Number);
-	    yyMinutes = 0;
+  case 13: /* iextime: tUNUMBER ':' tUNUMBER ':' tUNUMBER  */
+                                             {
+	    yyHour = (yyvsp[-4].Number);
+	    yyMinutes = (yyvsp[-2].Number);
+	    yySeconds = (yyvsp[0].Number);
+	}
+    break;
+
+  case 14: /* iextime: tUNUMBER ':' tUNUMBER  */
+                                {
+	    yyHour = (yyvsp[-2].Number);
+	    yyMinutes = (yyvsp[0].Number);
 	    yySeconds = 0;
-	    yyMeridian = (yyvsp[0].Meridian);
 	}
     break;
 
-  case 14: /* time: tUNUMBER ':' tUNUMBER o_merid  */
-                                        {
-	    yyHour = (yyvsp[-3].Number);
-	    yyMinutes = (yyvsp[-1].Number);
+  case 15: /* time: tUNUMBER tMERIDIAN  */
+                             {
+	    yyHour = (yyvsp[-1].Number);
+	    yyMinutes = 0;
 	    yySeconds = 0;
 	    yyMeridian = (yyvsp[0].Meridian);
 	}
     break;
 
-  case 15: /* time: tUNUMBER ':' tUNUMBER ':' tUNUMBER o_merid  */
-                                                     {
-	    yyHour = (yyvsp[-5].Number);
-	    yyMinutes = (yyvsp[-3].Number);
-	    yySeconds = (yyvsp[-1].Number);
+  case 16: /* time: iextime o_merid  */
+                          {
 	    yyMeridian = (yyvsp[0].Meridian);
 	}
     break;
 
-  case 16: /* zone: tZONE tDST  */
+  case 17: /* zone: tZONE tDST  */
                      {
 	    yyTimezone = (yyvsp[-1].Number);
-	    if (yyTimezone > HOUR( 12)) yyTimezone -= HOUR(100);
 	    yyDSTmode = DSTon;
 	}
     break;
 
-  case 17: /* zone: tZONE  */
+  case 18: /* zone: tZONE  */
                 {
 	    yyTimezone = (yyvsp[0].Number);
-	    if (yyTimezone > HOUR( 12)) yyTimezone -= HOUR(100);
 	    yyDSTmode = DSToff;
 	}
     break;
 
-  case 18: /* zone: tDAYZONE  */
+  case 19: /* zone: tDAYZONE  */
                    {
 	    yyTimezone = (yyvsp[0].Number);
 	    yyDSTmode = DSTon;
 	}
     break;
 
-  case 19: /* zone: sign tUNUMBER  */
-                        {
+  case 20: /* zone: tZONEwO4 sign INTNUM  */
+                               { /* GMT+0100, GMT-1000, etc. */
+	    yyTimezone = (yyvsp[-2].Number) - (yyvsp[-1].Number)*((yyvsp[0].Number) % 100 + ((yyvsp[0].Number) / 100) * 60);
+	    yyDSTmode = DSToff;
+	}
+    break;
+
+  case 21: /* zone: tZONEwO2 sign INTNUM  */
+                               { /* GMT+1, GMT-10, etc. */
+	    yyTimezone = (yyvsp[-2].Number) - (yyvsp[-1].Number)*((yyvsp[0].Number) * 60);
+	    yyDSTmode = DSToff;
+	}
+    break;
+
+  case 22: /* zone: sign INTNUM  */
+                      { /* +0100, -0100 */
 	    yyTimezone = -(yyvsp[-1].Number)*((yyvsp[0].Number) % 100 + ((yyvsp[0].Number) / 100) * 60);
 	    yyDSTmode = DSToff;
 	}
     break;
 
-  case 20: /* day: tDAY  */
+  case 25: /* day: tDAY  */
                {
 	    yyDayOrdinal = 1;
-	    yyDayNumber = (yyvsp[0].Number);
+	    yyDayOfWeek = (yyvsp[0].Number);
 	}
     break;
 
-  case 21: /* day: tDAY ','  */
-                   {
+  case 26: /* day: tDAY comma  */
+                     {
 	    yyDayOrdinal = 1;
-	    yyDayNumber = (yyvsp[-1].Number);
+	    yyDayOfWeek = (yyvsp[-1].Number);
 	}
     break;
 
-  case 22: /* day: tUNUMBER tDAY  */
+  case 27: /* day: tUNUMBER tDAY  */
                         {
 	    yyDayOrdinal = (yyvsp[-1].Number);
-	    yyDayNumber = (yyvsp[0].Number);
+	    yyDayOfWeek = (yyvsp[0].Number);
 	}
     break;
 
-  case 23: /* day: sign tUNUMBER tDAY  */
+  case 28: /* day: sign SP tUNUMBER tDAY  */
+                                {
+	    yyDayOrdinal = (yyvsp[-3].Number) * (yyvsp[-1].Number);
+	    yyDayOfWeek = (yyvsp[0].Number);
+	}
+    break;
+
+  case 29: /* day: sign tUNUMBER tDAY  */
                              {
 	    yyDayOrdinal = (yyvsp[-2].Number) * (yyvsp[-1].Number);
-	    yyDayNumber = (yyvsp[0].Number);
+	    yyDayOfWeek = (yyvsp[0].Number);
 	}
     break;
 
-  case 24: /* day: tNEXT tDAY  */
+  case 30: /* day: tNEXT tDAY  */
                      {
 	    yyDayOrdinal = 2;
-	    yyDayNumber = (yyvsp[0].Number);
+	    yyDayOfWeek = (yyvsp[0].Number);
+	}
+    break;
+
+  case 31: /* iexdate: tUNUMBER '-' tUNUMBER '-' tUNUMBER  */
+                                             {
+	    yyMonth = (yyvsp[-2].Number);
+	    yyDay = (yyvsp[0].Number);
+	    yyYear = (yyvsp[-4].Number);
 	}
     break;
 
-  case 25: /* date: tUNUMBER '/' tUNUMBER  */
+  case 32: /* date: tUNUMBER '/' tUNUMBER  */
                                 {
 	    yyMonth = (yyvsp[-2].Number);
 	    yyDay = (yyvsp[0].Number);
 	}
     break;
 
-  case 26: /* date: tUNUMBER '/' tUNUMBER '/' tUNUMBER  */
+  case 33: /* date: tUNUMBER '/' tUNUMBER '/' tUNUMBER  */
                                              {
 	    yyMonth = (yyvsp[-4].Number);
 	    yyDay = (yyvsp[-2].Number);
@@ -1656,15 +1657,7 @@ yyreduce:
 	}
     break;
 
-  case 27: /* date: tISOBASE  */
-                   {
-	    yyYear = (yyvsp[0].Number) / 10000;
-	    yyMonth = ((yyvsp[0].Number) % 10000)/100;
-	    yyDay = (yyvsp[0].Number) % 100;
-	}
-    break;
-
-  case 28: /* date: tUNUMBER '-' tMONTH '-' tUNUMBER  */
+  case 35: /* date: tUNUMBER '-' tMONTH '-' tUNUMBER  */
                                            {
 	    yyDay = (yyvsp[-4].Number);
 	    yyMonth = (yyvsp[-2].Number);
@@ -1672,37 +1665,29 @@ yyreduce:
 	}
     break;
 
-  case 29: /* date: tUNUMBER '-' tUNUMBER '-' tUNUMBER  */
-                                             {
-	    yyMonth = (yyvsp[-2].Number);
-	    yyDay = (yyvsp[0].Number);
-	    yyYear = (yyvsp[-4].Number);
-	}
-    break;
-
-  case 30: /* date: tMONTH tUNUMBER  */
+  case 36: /* date: tMONTH tUNUMBER  */
                           {
 	    yyMonth = (yyvsp[-1].Number);
 	    yyDay = (yyvsp[0].Number);
 	}
     break;
 
-  case 31: /* date: tMONTH tUNUMBER ',' tUNUMBER  */
-                                       {
+  case 37: /* date: tMONTH tUNUMBER comma tUNUMBER  */
+                                         {
 	    yyMonth = (yyvsp[-3].Number);
 	    yyDay = (yyvsp[-2].Number);
 	    yyYear = (yyvsp[0].Number);
 	}
     break;
 
-  case 32: /* date: tUNUMBER tMONTH  */
+  case 38: /* date: tUNUMBER tMONTH  */
                           {
 	    yyMonth = (yyvsp[0].Number);
 	    yyDay = (yyvsp[-1].Number);
 	}
     break;
 
-  case 33: /* date: tEPOCH  */
+  case 39: /* date: tEPOCH  */
                  {
 	    yyMonth = 1;
 	    yyDay = 1;
@@ -1710,7 +1695,7 @@ yyreduce:
 	}
     break;
 
-  case 34: /* date: tUNUMBER tMONTH tUNUMBER  */
+  case 40: /* date: tUNUMBER tMONTH tUNUMBER  */
                                    {
 	    yyMonth = (yyvsp[-1].Number);
 	    yyDay = (yyvsp[-2].Number);
@@ -1718,58 +1703,46 @@ yyreduce:
 	}
     break;
 
-  case 35: /* ordMonth: tNEXT tMONTH  */
+  case 41: /* ordMonth: tNEXT tMONTH  */
                        {
-	    yyMonthOrdinal = 1;
-	    yyMonth = (yyvsp[0].Number);
+	    yyMonthOrdinalIncr = 1;
+	    yyMonthOrdinal = (yyvsp[0].Number);
 	}
     break;
 
-  case 36: /* ordMonth: tNEXT tUNUMBER tMONTH  */
+  case 42: /* ordMonth: tNEXT tUNUMBER tMONTH  */
                                 {
-	    yyMonthOrdinal = (yyvsp[-1].Number);
-	    yyMonth = (yyvsp[0].Number);
+	    yyMonthOrdinalIncr = (yyvsp[-1].Number);
+	    yyMonthOrdinal = (yyvsp[0].Number);
 	}
     break;
 
-  case 37: /* iso: tUNUMBER '-' tUNUMBER '-' tUNUMBER tZONE tUNUMBER ':' tUNUMBER ':' tUNUMBER  */
-                                                   {
-	    if ((yyvsp[-5].Number) != HOUR( 7) + HOUR(100)) YYABORT;
-	    yyYear = (yyvsp[-10].Number);
-	    yyMonth = (yyvsp[-8].Number);
-	    yyDay = (yyvsp[-6].Number);
-	    yyHour = (yyvsp[-4].Number);
-	    yyMinutes = (yyvsp[-2].Number);
-	    yySeconds = (yyvsp[0].Number);
+  case 45: /* isodate: tISOBAS8  */
+                   { /* YYYYMMDD */
+	    yyYear = (yyvsp[0].Number) / 10000;
+	    yyMonth = ((yyvsp[0].Number) % 10000)/100;
+	    yyDay = (yyvsp[0].Number) % 100;
 	}
     break;
 
-  case 38: /* iso: tISOBASE tZONE tISOBASE  */
-                                  {
-	    if ((yyvsp[-1].Number) != HOUR( 7) + HOUR(100)) YYABORT;
-	    yyYear = (yyvsp[-2].Number) / 10000;
-	    yyMonth = ((yyvsp[-2].Number) % 10000)/100;
-	    yyDay = (yyvsp[-2].Number) % 100;
-	    yyHour = (yyvsp[0].Number) / 10000;
-	    yyMinutes = ((yyvsp[0].Number) % 10000)/100;
-	    yySeconds = (yyvsp[0].Number) % 100;
+  case 46: /* isodate: tISOBAS6  */
+                   { /* YYMMDD */
+	    yyYear = (yyvsp[0].Number) / 10000;
+	    yyMonth = ((yyvsp[0].Number) % 10000)/100;
+	    yyDay = (yyvsp[0].Number) % 100;
 	}
     break;
 
-  case 39: /* iso: tISOBASE tZONE tUNUMBER ':' tUNUMBER ':' tUNUMBER  */
-                                                            {
-	    if ((yyvsp[-5].Number) != HOUR( 7) + HOUR(100)) YYABORT;
-	    yyYear = (yyvsp[-6].Number) / 10000;
-	    yyMonth = ((yyvsp[-6].Number) % 10000)/100;
-	    yyDay = (yyvsp[-6].Number) % 100;
-	    yyHour = (yyvsp[-4].Number);
-	    yyMinutes = (yyvsp[-2].Number);
-	    yySeconds = (yyvsp[0].Number);
+  case 48: /* isotime: tISOBAS6  */
+                   {
+	    yyHour = (yyvsp[0].Number) / 10000;
+	    yyMinutes = ((yyvsp[0].Number) % 10000)/100;
+	    yySeconds = (yyvsp[0].Number) % 100;
 	}
     break;
 
-  case 40: /* iso: tISOBASE tISOBASE  */
-                            {
+  case 51: /* iso: tISOBASL tISOBAS6  */
+                            { /* YYYYMMDDhhmmss */
 	    yyYear = (yyvsp[-1].Number) / 10000;
 	    yyMonth = ((yyvsp[-1].Number) % 10000)/100;
 	    yyDay = (yyvsp[-1].Number) % 100;
@@ -1779,8 +1752,20 @@ yyreduce:
 	}
     break;
 
-  case 41: /* trek: tSTARDATE tUNUMBER '.' tUNUMBER  */
-                                          {
+  case 52: /* iso: tISOBASL tUNUMBER  */
+                            { /* YYYYMMDDhhmm */
+	    if (yyDigitCount != 4) YYABORT; /* normally unreached */
+	    yyYear = (yyvsp[-1].Number) / 10000;
+	    yyMonth = ((yyvsp[-1].Number) % 10000)/100;
+	    yyDay = (yyvsp[-1].Number) % 100;
+	    yyHour = (yyvsp[0].Number) / 100;
+	    yyMinutes = ((yyvsp[0].Number) % 100);
+	    yySeconds = 0;
+	}
+    break;
+
+  case 53: /* trek: tSTARDATE INTNUM '.' tUNUMBER  */
+                                        {
 	    /*
 	     * Offset computed year by -377 so that the returned years will be
 	     * in a range accessible with a 32 bit clock seconds value.
@@ -1790,11 +1775,11 @@ yyreduce:
 	    yyDay  = 1;
 	    yyMonth = 1;
 	    yyRelDay += (((yyvsp[-2].Number)%1000)*(365 + IsLeapYear(yyYear)))/1000;
-	    yyRelSeconds += (yyvsp[0].Number) * 144 * 60;
+	    yyRelSeconds += (yyvsp[0].Number) * (144LL * 60LL);
 	}
     break;
 
-  case 42: /* relspec: relunits tAGO  */
+  case 54: /* relspec: relunits tAGO  */
                         {
 	    yyRelSeconds *= -1;
 	    yyRelMonth *= -1;
@@ -1802,75 +1787,99 @@ yyreduce:
 	}
     break;
 
-  case 44: /* relunits: sign tUNUMBER unit  */
-                              {
+  case 56: /* relunits: sign SP INTNUM unit  */
+                               {
+	    *yyRelPointer += (yyvsp[-3].Number) * (yyvsp[-1].Number) * (yyvsp[0].Number);
+	}
+    break;
+
+  case 57: /* relunits: sign INTNUM unit  */
+                           {
 	    *yyRelPointer += (yyvsp[-2].Number) * (yyvsp[-1].Number) * (yyvsp[0].Number);
 	}
     break;
 
-  case 45: /* relunits: tUNUMBER unit  */
-                        {
+  case 58: /* relunits: INTNUM unit  */
+                      {
 	    *yyRelPointer += (yyvsp[-1].Number) * (yyvsp[0].Number);
 	}
     break;
 
-  case 46: /* relunits: tNEXT unit  */
+  case 59: /* relunits: tNEXT unit  */
                      {
 	    *yyRelPointer += (yyvsp[0].Number);
 	}
     break;
 
-  case 47: /* relunits: tNEXT tUNUMBER unit  */
-                              {
+  case 60: /* relunits: tNEXT INTNUM unit  */
+                            {
 	    *yyRelPointer += (yyvsp[-1].Number) * (yyvsp[0].Number);
 	}
     break;
 
-  case 48: /* relunits: unit  */
+  case 61: /* relunits: unit  */
                {
 	    *yyRelPointer += (yyvsp[0].Number);
 	}
     break;
 
-  case 49: /* sign: '-'  */
+  case 62: /* sign: '-'  */
               {
 	    (yyval.Number) = -1;
 	}
     break;
 
-  case 50: /* sign: '+'  */
+  case 63: /* sign: '+'  */
               {
 	    (yyval.Number) =  1;
 	}
     break;
 
-  case 51: /* unit: tSEC_UNIT  */
+  case 64: /* unit: tSEC_UNIT  */
                     {
 	    (yyval.Number) = (yyvsp[0].Number);
 	    yyRelPointer = &yyRelSeconds;
 	}
     break;
 
-  case 52: /* unit: tDAY_UNIT  */
+  case 65: /* unit: tDAY_UNIT  */
                     {
 	    (yyval.Number) = (yyvsp[0].Number);
 	    yyRelPointer = &yyRelDay;
 	}
     break;
 
-  case 53: /* unit: tMONTH_UNIT  */
+  case 66: /* unit: tMONTH_UNIT  */
                       {
 	    (yyval.Number) = (yyvsp[0].Number);
 	    yyRelPointer = &yyRelMonth;
 	}
     break;
 
-  case 54: /* number: tUNUMBER  */
+  case 67: /* INTNUM: tUNUMBER  */
                    {
-	    if (yyHaveTime && yyHaveDate && !yyHaveRel) {
+	    (yyval.Number) = (yyvsp[0].Number);
+	}
+    break;
+
+  case 68: /* INTNUM: tISOBAS6  */
+                   {
+	    (yyval.Number) = (yyvsp[0].Number);
+	}
+    break;
+
+  case 69: /* INTNUM: tISOBAS8  */
+                   {
+	    (yyval.Number) = (yyvsp[0].Number);
+	}
+    break;
+
+  case 70: /* numitem: tUNUMBER  */
+                   {
+	    if ((info->flags & (CLF_TIME|CLF_HAVEDATE|CLF_RELCONV)) == (CLF_TIME|CLF_HAVEDATE)) {
 		yyYear = (yyvsp[0].Number);
 	    } else {
-		yyHaveTime++;
+		yyIncrFlags(CLF_TIME);
 		if (yyDigitCount <= 2) {
 		    yyHour = (yyvsp[0].Number);
 		    yyMinutes = 0;
@@ -1884,13 +1893,13 @@ yyreduce:
 	}
     break;
 
-  case 55: /* o_merid: %empty  */
+  case 71: /* o_merid: %empty  */
                      {
 	    (yyval.Meridian) = MER24;
 	}
     break;
 
-  case 56: /* o_merid: tMERIDIAN  */
+  case 72: /* o_merid: tMERIDIAN  */
                     {
 	    (yyval.Meridian) = (yyvsp[0].Meridian);
 	}
@@ -2155,20 +2164,6 @@ static const TABLE OtherTable[] = {
     { "last",		tUNUMBER,	-1 },
     { "this",		tSEC_UNIT,	0 },
     { "next",		tNEXT,		1 },
-#if 0
-    { "first",		tUNUMBER,	1 },
-    { "second",		tUNUMBER,	2 },
-    { "third",		tUNUMBER,	3 },
-    { "fourth",		tUNUMBER,	4 },
-    { "fifth",		tUNUMBER,	5 },
-    { "sixth",		tUNUMBER,	6 },
-    { "seventh",	tUNUMBER,	7 },
-    { "eighth",		tUNUMBER,	8 },
-    { "ninth",		tUNUMBER,	9 },
-    { "tenth",		tUNUMBER,	10 },
-    { "eleventh",	tUNUMBER,	11 },
-    { "twelfth",	tUNUMBER,	12 },
-#endif
     { "ago",		tAGO,		1 },
     { "epoch",		tEPOCH,		0 },
     { "stardate",	tSTARDATE,	0 },
@@ -2268,34 +2263,44 @@ static const TABLE TimezoneTable[] = {
  */
 
 static const TABLE MilitaryTable[] = {
-    { "a",	tZONE,	-HOUR( 1) + HOUR(100) },
-    { "b",	tZONE,	-HOUR( 2) + HOUR(100) },
-    { "c",	tZONE,	-HOUR( 3) + HOUR(100) },
-    { "d",	tZONE,	-HOUR( 4) + HOUR(100) },
-    { "e",	tZONE,	-HOUR( 5) + HOUR(100) },
-    { "f",	tZONE,	-HOUR( 6) + HOUR(100) },
-    { "g",	tZONE,	-HOUR( 7) + HOUR(100) },
-    { "h",	tZONE,	-HOUR( 8) + HOUR(100) },
-    { "i",	tZONE,	-HOUR( 9) + HOUR(100) },
-    { "k",	tZONE,	-HOUR(10) + HOUR(100) },
-    { "l",	tZONE,	-HOUR(11) + HOUR(100) },
-    { "m",	tZONE,	-HOUR(12) + HOUR(100) },
-    { "n",	tZONE,	HOUR(  1) + HOUR(100) },
-    { "o",	tZONE,	HOUR(  2) + HOUR(100) },
-    { "p",	tZONE,	HOUR(  3) + HOUR(100) },
-    { "q",	tZONE,	HOUR(  4) + HOUR(100) },
-    { "r",	tZONE,	HOUR(  5) + HOUR(100) },
-    { "s",	tZONE,	HOUR(  6) + HOUR(100) },
-    { "t",	tZONE,	HOUR(  7) + HOUR(100) },
-    { "u",	tZONE,	HOUR(  8) + HOUR(100) },
-    { "v",	tZONE,	HOUR(  9) + HOUR(100) },
-    { "w",	tZONE,	HOUR( 10) + HOUR(100) },
-    { "x",	tZONE,	HOUR( 11) + HOUR(100) },
-    { "y",	tZONE,	HOUR( 12) + HOUR(100) },
-    { "z",	tZONE,	HOUR( 0)  + HOUR(100) },
+    { "a",	tZONE,	-HOUR( 1) },
+    { "b",	tZONE,	-HOUR( 2) },
+    { "c",	tZONE,	-HOUR( 3) },
+    { "d",	tZONE,	-HOUR( 4) },
+    { "e",	tZONE,	-HOUR( 5) },
+    { "f",	tZONE,	-HOUR( 6) },
+    { "g",	tZONE,	-HOUR( 7) },
+    { "h",	tZONE,	-HOUR( 8) },
+    { "i",	tZONE,	-HOUR( 9) },
+    { "k",	tZONE,	-HOUR(10) },
+    { "l",	tZONE,	-HOUR(11) },
+    { "m",	tZONE,	-HOUR(12) },
+    { "n",	tZONE,	HOUR(  1) },
+    { "o",	tZONE,	HOUR(  2) },
+    { "p",	tZONE,	HOUR(  3) },
+    { "q",	tZONE,	HOUR(  4) },
+    { "r",	tZONE,	HOUR(  5) },
+    { "s",	tZONE,	HOUR(  6) },
+    { "t",	tZONE,	HOUR(  7) },
+    { "u",	tZONE,	HOUR(  8) },
+    { "v",	tZONE,	HOUR(  9) },
+    { "w",	tZONE,	HOUR( 10) },
+    { "x",	tZONE,	HOUR( 11) },
+    { "y",	tZONE,	HOUR( 12) },
+    { "z",	tZONE,	HOUR( 0) },
     { NULL, 0, 0 }
 };
 
+static inline const char *
+bypassSpaces(
+    const char *s)
+{
+    while (TclIsSpaceProc(*s)) {
+	s++;
+    }
+    return s;
+}
+
 /*
  * Dump error messages in the bit bucket.
  */
@@ -2307,6 +2312,9 @@ TclDateerror(
     const char *s)
 {
     Tcl_Obj* t;
+    if (!infoPtr->messages) {
+	TclNewObj(infoPtr->messages);
+    }
     Tcl_AppendToObj(infoPtr->messages, infoPtr->separatrix, -1);
     Tcl_AppendToObj(infoPtr->messages, s, -1);
     Tcl_AppendToObj(infoPtr->messages, " (characters ", -1);
@@ -2323,11 +2331,11 @@ TclDateerror(
     infoPtr->separatrix = "\n";
 }
 
-static time_t
+int
 ToSeconds(
-    time_t Hours,
-    time_t Minutes,
-    time_t Seconds,
+    int Hours,
+    int Minutes,
+    int Seconds,
     MERIDIAN Meridian)
 {
     if (Minutes < 0 || Minutes > 59 || Seconds < 0 || Seconds > 59) {
@@ -2338,17 +2346,17 @@ ToSeconds(
 	if (Hours < 0 || Hours > 23) {
 	    return -1;
 	}
-	return (Hours * 60L + Minutes) * 60L + Seconds;
+	return (Hours * 60 + Minutes) * 60 + Seconds;
     case MERam:
 	if (Hours < 1 || Hours > 12) {
 	    return -1;
 	}
-	return ((Hours % 12) * 60L + Minutes) * 60L + Seconds;
+	return ((Hours % 12) * 60 + Minutes) * 60 + Seconds;
     case MERpm:
 	if (Hours < 1 || Hours > 12) {
 	    return -1;
 	}
-	return (((Hours % 12) + 12) * 60L + Minutes) * 60L + Seconds;
+	return (((Hours % 12) + 12) * 60 + Minutes) * 60 + Seconds;
     }
     return -1;			/* Should never be reached */
 }
@@ -2369,11 +2377,11 @@ LookupWord(
 
     Tcl_UtfToLower(buff);
 
-    if (strcmp(buff, "am") == 0 || strcmp(buff, "a.m.") == 0) {
+    if (*buff == 'a' && (strcmp(buff, "am") == 0 || strcmp(buff, "a.m.") == 0)) {
 	yylvalPtr->Meridian = MERam;
 	return tMERIDIAN;
     }
-    if (strcmp(buff, "pm") == 0 || strcmp(buff, "p.m.") == 0) {
+    if (*buff == 'p' && (strcmp(buff, "pm") == 0 || strcmp(buff, "p.m.") == 0)) {
 	yylvalPtr->Meridian = MERpm;
 	return tMERIDIAN;
     }
@@ -2487,50 +2495,114 @@ TclDatelex(
     char *p;
     char buff[20];
     int Count;
+    const char *tokStart;
 
     location->first_column = yyInput - info->dateStart;
     for ( ; ; ) {
-	while (TclIsSpaceProcM(*yyInput)) {
-	    yyInput++;
+
+	if (isspace(UCHAR(*yyInput))) {
+	    yyInput = bypassSpaces(yyInput);
+	    /* ignore space at end of text and before some words */
+	    c = *yyInput;
+	    if (c != '\0' && !isalpha(UCHAR(c))) {
+		return SP;
+	    }
 	}
+	tokStart = yyInput;
 
 	if (isdigit(UCHAR(c = *yyInput))) { /* INTL: digit */
+
 	    /*
 	     * Convert the string into a number; count the number of digits.
 	     */
-
-	    Count = 0;
-	    for (yylvalPtr->Number = 0;
-		    isdigit(UCHAR(c = *yyInput++)); ) {	  /* INTL: digit */
-		yylvalPtr->Number = 10 * yylvalPtr->Number + c - '0';
-		Count++;
+	    long long num = c - '0';
+	    p = (char *)yyInput;
+	    while (isdigit(UCHAR(c = *(++p)))) {
+		if (num >= 0) {
+		    num *= 10; num += c - '0';
+		}
 	    }
-	    yyInput--;
-	    yyDigitCount = Count;
+	    yylvalPtr->Number = num;
+	    yyDigitCount = p - yyInput;
+	    yyInput = p;
 
 	    /*
 	     * A number with 6 or more digits is considered an ISO 8601 base.
 	     */
 
-	    if (Count >= 6) {
-		location->last_column = yyInput - info->dateStart - 1;
-		return tISOBASE;
-	    } else {
-		location->last_column = yyInput - info->dateStart - 1;
-		return tUNUMBER;
+	    location->last_column = yyInput - info->dateStart - 1;
+	    if (yyDigitCount >= 6) {
+		if (yyDigitCount == 14 || yyDigitCount == 12) {
+		    /* long form of ISO 8601 (without separator), either
+		     * YYYYMMDDhhmmss or YYYYMMDDhhmm, so reduce to date
+		     * (8 chars is isodate) */
+		    p = (char *)tokStart;
+		    num = *p++ - '0';
+		    do {
+			num *= 10; num += *p++ - '0';
+		    } while (p - tokStart < 8);
+		    yylvalPtr->Number = num;
+		    yyDigitCount = 8;
+		    yyInput = p;
+		    location->last_column = yyInput - info->dateStart - 1;
+		    return tISOBASL;
+		}
+		if (yyDigitCount > 14) { /* overflow */
+		    return tID;
+		}
+		if (yyDigitCount == 8) {
+		    return tISOBAS8;
+		}
+		if (yyDigitCount == 6) {
+		    return tISOBAS6;
+		}
 	    }
+	    /* ignore spaces after digits (optional) */
+	    yyInput = bypassSpaces(yyInput);
+	    return tUNUMBER;
 	}
 	if (!(c & 0x80) && isalpha(UCHAR(c))) {		  /* INTL: ISO only. */
+	    int ret;
 	    for (p = buff; isalpha(UCHAR(c = *yyInput++)) /* INTL: ISO only. */
 		     || c == '.'; ) {
-		if (p < &buff[sizeof buff - 1]) {
+		if (p < &buff[sizeof(buff) - 1]) {
 		    *p++ = c;
 		}
 	    }
 	    *p = '\0';
 	    yyInput--;
 	    location->last_column = yyInput - info->dateStart - 1;
-	    return LookupWord(yylvalPtr, buff);
+	    ret = LookupWord(yylvalPtr, buff);
+	    /*
+	     * lookahead:
+	     *	for spaces to consider word boundaries (for instance
+	     *	literal T in isodateTisotimeZ is not a TZ, but Z is UTC);
+	     *	for +/- digit, to differentiate between "GMT+1000 day" and "GMT +1000 day";
+	     * bypass spaces after token (but ignore by TZ+OFFS), because should
+	     * recognize next SP token, if TZ only.
+	     */
+	    if (ret == tZONE || ret == tDAYZONE) {
+		c = *yyInput;
+		if (isdigit(UCHAR(c))) { /* literal not a TZ  */
+		    yyInput = tokStart;
+		    return *yyInput++;
+		}
+		if ((c == '+' || c == '-') && isdigit(UCHAR(*(yyInput+1)))) {
+		    if ( !isdigit(UCHAR(*(yyInput+2)))
+		      || !isdigit(UCHAR(*(yyInput+3)))) {
+			/* GMT+1, GMT-10, etc. */
+			return tZONEwO2;
+		    }
+		    if ( isdigit(UCHAR(*(yyInput+4)))
+		      && !isdigit(UCHAR(*(yyInput+5)))) {
+			/* GMT+1000, etc. */
+			return tZONEwO4;
+		    }
+		}
+	    }
+	    yyInput = bypassSpaces(yyInput);
+	    return ret;
+
 	}
 	if (c != '(') {
 	    location->last_column = yyInput - info->dateStart;
@@ -2550,169 +2622,75 @@ TclDatelex(
 	} while (Count > 0);
     }
 }
-
+
 int
-TclClockOldscanObjCmd(
-    TCL_UNUSED(void *),
+TclClockFreeScan(
     Tcl_Interp *interp,		/* Tcl interpreter */
-    int objc,			/* Count of parameters */
-    Tcl_Obj *const *objv)	/* Parameters */
+    DateInfo *info)		/* Input and result parameters */
 {
-    Tcl_Obj *result, *resultElement;
-    int yr, mo, da;
-    DateInfo dateInfo;
-    DateInfo* info = &dateInfo;
     int status;
 
-    if (objc != 5) {
-	Tcl_WrongNumArgs(interp, 1, objv,
-		"stringToParse baseYear baseMonth baseDay" );
-	return TCL_ERROR;
-    }
-
-    yyInput = TclGetString(objv[1]);
-    dateInfo.dateStart = yyInput;
-
-    yyHaveDate = 0;
-    if (Tcl_GetIntFromObj(interp, objv[2], &yr) != TCL_OK
-	    || Tcl_GetIntFromObj(interp, objv[3], &mo) != TCL_OK
-	    || Tcl_GetIntFromObj(interp, objv[4], &da) != TCL_OK) {
-	return TCL_ERROR;
-    }
-    yyYear = yr; yyMonth = mo; yyDay = da;
-
-    yyHaveTime = 0;
-    yyHour = 0; yyMinutes = 0; yySeconds = 0; yyMeridian = MER24;
+  #if YYDEBUG
+    /* enable debugging if compiled with YYDEBUG */
+    yydebug = 1;
+  #endif
 
-    yyHaveZone = 0;
-    yyTimezone = 0; yyDSTmode = DSTmaybe;
+    /*
+     * yyInput = stringToParse;
+     *
+     * ClockInitDateInfo(info) should be executed to pre-init info;
+     */
 
-    yyHaveOrdinalMonth = 0;
-    yyMonthOrdinal = 0;
+    yyDSTmode = DSTmaybe;
 
-    yyHaveDay = 0;
-    yyDayOrdinal = 0; yyDayNumber = 0;
+    info->separatrix = "";
 
-    yyHaveRel = 0;
-    yyRelMonth = 0; yyRelDay = 0; yyRelSeconds = 0; yyRelPointer = NULL;
+    info->dateStart = yyInput;
 
-    TclNewObj(dateInfo.messages);
-    dateInfo.separatrix = "";
-    Tcl_IncrRefCount(dateInfo.messages);
+    /* ignore spaces at begin */
+    yyInput = bypassSpaces(yyInput);
 
-    status = yyparse(&dateInfo);
+    /* parse */
+    status = yyparse(info);
     if (status == 1) {
-	Tcl_SetObjResult(interp, dateInfo.messages);
-	Tcl_DecrRefCount(dateInfo.messages);
-	Tcl_SetErrorCode(interp, "TCL", "VALUE", "DATE", "PARSE", (char *)NULL);
-	return TCL_ERROR;
+    	const char *msg = NULL;
+	if (info->errFlags & CLF_HAVEDATE) {
+	    msg = "more than one date in string";
+	} else if (info->errFlags & CLF_TIME) {
+	    msg = "more than one time of day in string";
+	} else if (info->errFlags & CLF_ZONE) {
+	    msg = "more than one time zone in string";
+	} else if (info->errFlags & CLF_DAYOFWEEK) {
+	    msg = "more than one weekday in string";
+	} else if (info->errFlags & CLF_ORDINALMONTH) {
+	    msg = "more than one ordinal month in string";
+	}
+	if (msg) {
+	    Tcl_SetObjResult(interp, Tcl_NewStringObj(msg, -1));
+	    Tcl_SetErrorCode(interp, "TCL", "VALUE", "DATE", "MULTIPLE", (char *)NULL);
+	} else {
+	    Tcl_SetObjResult(interp,
+		info->messages ? info->messages : Tcl_NewObj());
+	    info->messages = NULL;
+	    Tcl_SetErrorCode(interp, "TCL", "VALUE", "DATE", "PARSE", (char *)NULL);
+	}
+	status = TCL_ERROR;
     } else if (status == 2) {
 	Tcl_SetObjResult(interp, Tcl_NewStringObj("memory exhausted", -1));
-	Tcl_DecrRefCount(dateInfo.messages);
 	Tcl_SetErrorCode(interp, "TCL", "MEMORY", (char *)NULL);
-	return TCL_ERROR;
+	status = TCL_ERROR;
     } else if (status != 0) {
 	Tcl_SetObjResult(interp, Tcl_NewStringObj("Unknown status returned "
 						  "from date parser. Please "
 						  "report this error as a "
 						  "bug in Tcl.", -1));
-	Tcl_DecrRefCount(dateInfo.messages);
 	Tcl_SetErrorCode(interp, "TCL", "BUG", (char *)NULL);
-	return TCL_ERROR;
-    }
-    Tcl_DecrRefCount(dateInfo.messages);
-
-    if (yyHaveDate > 1) {
-	Tcl_SetObjResult(interp,
-		Tcl_NewStringObj("more than one date in string", -1));
-	Tcl_SetErrorCode(interp, "TCL", "VALUE", "DATE", "MULTIPLE", (char *)NULL);
-	return TCL_ERROR;
-    }
-    if (yyHaveTime > 1) {
-	Tcl_SetObjResult(interp,
-		Tcl_NewStringObj("more than one time of day in string", -1));
-	Tcl_SetErrorCode(interp, "TCL", "VALUE", "DATE", "MULTIPLE", (char *)NULL);
-	return TCL_ERROR;
-    }
-    if (yyHaveZone > 1) {
-	Tcl_SetObjResult(interp,
-		Tcl_NewStringObj("more than one time zone in string", -1));
-	Tcl_SetErrorCode(interp, "TCL", "VALUE", "DATE", "MULTIPLE", (char *)NULL);
-	return TCL_ERROR;
-    }
-    if (yyHaveDay > 1) {
-	Tcl_SetObjResult(interp,
-		Tcl_NewStringObj("more than one weekday in string", -1));
-	Tcl_SetErrorCode(interp, "TCL", "VALUE", "DATE", "MULTIPLE", (char *)NULL);
-	return TCL_ERROR;
+	status = TCL_ERROR;
     }
-    if (yyHaveOrdinalMonth > 1) {
-	Tcl_SetObjResult(interp,
-		Tcl_NewStringObj("more than one ordinal month in string", -1));
-	Tcl_SetErrorCode(interp, "TCL", "VALUE", "DATE", "MULTIPLE", (char *)NULL);
-	return TCL_ERROR;
+    if (info->messages) {
+	Tcl_DecrRefCount(info->messages);
     }
-
-    TclNewObj(result);
-    TclNewObj(resultElement);
-    if (yyHaveDate) {
-	Tcl_ListObjAppendElement(interp, resultElement,
-		Tcl_NewIntObj(yyYear));
-	Tcl_ListObjAppendElement(interp, resultElement,
-		Tcl_NewIntObj(yyMonth));
-	Tcl_ListObjAppendElement(interp, resultElement,
-		Tcl_NewIntObj(yyDay));
-    }
-    Tcl_ListObjAppendElement(interp, result, resultElement);
-
-    if (yyHaveTime) {
-	Tcl_ListObjAppendElement(interp, result, Tcl_NewIntObj(
-		ToSeconds(yyHour, yyMinutes, yySeconds, (MERIDIAN)yyMeridian)));
-    } else {
-	TclNewObj(resultElement);
-	Tcl_ListObjAppendElement(interp, result, resultElement);
-    }
-
-    TclNewObj(resultElement);
-    if (yyHaveZone) {
-	Tcl_ListObjAppendElement(interp, resultElement,
-		Tcl_NewIntObj(-yyTimezone));
-	Tcl_ListObjAppendElement(interp, resultElement,
-		Tcl_NewIntObj(1 - yyDSTmode));
-    }
-    Tcl_ListObjAppendElement(interp, result, resultElement);
-
-    TclNewObj(resultElement);
-    if (yyHaveRel) {
-	Tcl_ListObjAppendElement(interp, resultElement,
-		Tcl_NewIntObj(yyRelMonth));
-	Tcl_ListObjAppendElement(interp, resultElement,
-		Tcl_NewIntObj(yyRelDay));
-	Tcl_ListObjAppendElement(interp, resultElement,
-		Tcl_NewIntObj(yyRelSeconds));
-    }
-    Tcl_ListObjAppendElement(interp, result, resultElement);
-
-    TclNewObj(resultElement);
-    if (yyHaveDay && !yyHaveDate) {
-	Tcl_ListObjAppendElement(interp, resultElement,
-		Tcl_NewIntObj(yyDayOrdinal));
-	Tcl_ListObjAppendElement(interp, resultElement,
-		Tcl_NewIntObj(yyDayNumber));
-    }
-    Tcl_ListObjAppendElement(interp, result, resultElement);
-
-    TclNewObj(resultElement);
-    if (yyHaveOrdinalMonth) {
-	Tcl_ListObjAppendElement(interp, resultElement,
-		Tcl_NewIntObj(yyMonthOrdinal));
-	Tcl_ListObjAppendElement(interp, resultElement,
-		Tcl_NewIntObj(yyMonth));
-    }
-    Tcl_ListObjAppendElement(interp, result, resultElement);
-
-    Tcl_SetObjResult(interp, result);
-    return TCL_OK;
+    return status;
 }
 
 /*
diff --git a/generic/tclDate.h b/generic/tclDate.h
new file mode 100644
index 0000000..81910ff
--- /dev/null
+++ b/generic/tclDate.h
@@ -0,0 +1,569 @@
+/*
+ * tclDate.h --
+ *
+ *	This header file handles common usage of clock primitives
+ *	between tclDate.c (yacc), tclClock.c and tclClockFmt.c.
+ *
+ * Copyright (c) 2014 Serg G. Brester (aka sebres)
+ *
+ * See the file "license.terms" for information on usage and redistribution
+ * of this file, and for a DISCLAIMER OF ALL WARRANTIES.
+ */
+
+#ifndef _TCLCLOCK_H
+#define _TCLCLOCK_H
+
+/*
+ * Constants
+ */
+
+#define JULIAN_DAY_POSIX_EPOCH		2440588
+#define GREGORIAN_CHANGE_DATE		2361222
+#define SECONDS_PER_DAY			86400
+#define JULIAN_SEC_POSIX_EPOCH	      (((Tcl_WideInt) JULIAN_DAY_POSIX_EPOCH) \
+					* SECONDS_PER_DAY)
+#define FOUR_CENTURIES			146097	/* days */
+#define JDAY_1_JAN_1_CE_JULIAN		1721424
+#define JDAY_1_JAN_1_CE_GREGORIAN	1721426
+#define ONE_CENTURY_GREGORIAN		36524	/* days */
+#define FOUR_YEARS			1461	/* days */
+#define ONE_YEAR			365	/* days */
+
+#define RODDENBERRY			1946	/* Another epoch (Hi, Jeff!) */
+
+
+#define CLF_OPTIONAL	       (1 << 0) /* token is non mandatory */
+#define CLF_POSIXSEC	       (1 << 1)
+#define CLF_LOCALSEC	       (1 << 2)
+#define CLF_JULIANDAY	       (1 << 3)
+#define CLF_TIME	       (1 << 4)
+#define CLF_ZONE	       (1 << 5)
+#define CLF_CENTURY	       (1 << 6)
+#define CLF_DAYOFMONTH	       (1 << 7)
+#define CLF_DAYOFYEAR	       (1 << 8)
+#define CLF_MONTH	       (1 << 9)
+#define CLF_YEAR	       (1 << 10)
+#define CLF_DAYOFWEEK	       (1 << 11)
+#define CLF_ISO8601YEAR	       (1 << 12)
+#define CLF_ISO8601WEAK	       (1 << 13)
+#define CLF_ISO8601CENTURY     (1 << 14)
+
+#define CLF_SIGNED	       (1 << 15)
+
+/* extra flags used outside of scan/format-tokens too (int, not a short int) */
+#define CLF_RELCONV	       (1 << 17)
+#define CLF_ORDINALMONTH       (1 << 18)
+
+/* On demand (lazy) assemble flags */
+#define CLF_ASSEMBLE_DATE      (1 << 28) /* assemble year, month, etc. using julianDay */
+#define CLF_ASSEMBLE_JULIANDAY (1 << 29) /* assemble julianDay using year, month, etc. */
+#define CLF_ASSEMBLE_SECONDS   (1 << 30) /* assemble localSeconds (and seconds at end) */
+
+#define CLF_HAVEDATE	       (CLF_DAYOFMONTH|CLF_MONTH|CLF_YEAR)
+#define CLF_DATE	       (CLF_JULIANDAY | CLF_DAYOFMONTH | CLF_DAYOFYEAR | \
+				CLF_MONTH | CLF_YEAR | CLF_ISO8601YEAR | \
+				CLF_DAYOFWEEK | CLF_ISO8601WEAK)
+
+#define TCL_MIN_SECONDS			-0x00F0000000000000L
+#define TCL_MAX_SECONDS			 0x00F0000000000000L
+#define TCL_INV_SECONDS			(TCL_MIN_SECONDS-1)
+
+/*
+ * Enumeration of the string literals used in [clock]
+ */
+
+typedef enum ClockLiteral {
+    LIT__NIL,
+    LIT__DEFAULT_FORMAT,
+    LIT_SYSTEM,		LIT_CURRENT,		LIT_C,
+    LIT_BCE,		LIT_CE,
+    LIT_DAYOFMONTH,	LIT_DAYOFWEEK,		LIT_DAYOFYEAR,
+    LIT_ERA,		LIT_GMT,		LIT_GREGORIAN,
+    LIT_INTEGER_VALUE_TOO_LARGE,
+    LIT_ISO8601WEEK,	LIT_ISO8601YEAR,
+    LIT_JULIANDAY,	LIT_LOCALSECONDS,
+    LIT_MONTH,
+    LIT_SECONDS,	LIT_TZNAME,		LIT_TZOFFSET,
+    LIT_YEAR,
+    LIT_TZDATA,
+    LIT_GETSYSTEMTIMEZONE,
+    LIT_SETUPTIMEZONE,
+    LIT_MCGET,
+    LIT_GETSYSTEMLOCALE, LIT_GETCURRENTLOCALE,
+    LIT_LOCALIZE_FORMAT,
+    LIT__END
+} ClockLiteral;
+
+#define CLOCK_LITERAL_ARRAY(litarr) static const char *const litarr[] = { \
+    "", \
+    "%a %b %d %H:%M:%S %Z %Y", \
+    "system",		"current",		"C", \
+    "BCE",		"CE", \
+    "dayOfMonth",	"dayOfWeek",		"dayOfYear", \
+    "era",		":GMT",			"gregorian", \
+    "integer value too large to represent", \
+    "iso8601Week",	"iso8601Year", \
+    "julianDay",	"localSeconds", \
+    "month", \
+    "seconds",		"tzName",		"tzOffset", \
+    "year", \
+    "::tcl::clock::TZData", \
+    "::tcl::clock::GetSystemTimeZone", \
+    "::tcl::clock::SetupTimeZone", \
+    "::tcl::clock::mcget", \
+    "::tcl::clock::GetSystemLocale", "::tcl::clock::mclocale", \
+    "::tcl::clock::LocalizeFormat" \
+}
+
+/*
+ * Enumeration of the msgcat literals used in [clock]
+ */
+
+typedef enum ClockMsgCtLiteral {
+    MCLIT__NIL, /* placeholder */
+    MCLIT_MONTHS_FULL,	MCLIT_MONTHS_ABBREV,  MCLIT_MONTHS_COMB,
+    MCLIT_DAYS_OF_WEEK_FULL,  MCLIT_DAYS_OF_WEEK_ABBREV,  MCLIT_DAYS_OF_WEEK_COMB,
+    MCLIT_AM,  MCLIT_PM,
+    MCLIT_LOCALE_ERAS,
+    MCLIT_BCE,	 MCLIT_CE,
+    MCLIT_BCE2,	 MCLIT_CE2,
+    MCLIT_BCE3,	 MCLIT_CE3,
+    MCLIT_LOCALE_NUMERALS,
+    MCLIT__END
+} ClockMsgCtLiteral;
+
+#define CLOCK_LOCALE_LITERAL_ARRAY(litarr, pref) static const char *const litarr[] = { \
+    pref "", \
+    pref "MONTHS_FULL", pref "MONTHS_ABBREV", pref "MONTHS_COMB", \
+    pref "DAYS_OF_WEEK_FULL", pref "DAYS_OF_WEEK_ABBREV", pref "DAYS_OF_WEEK_COMB", \
+    pref "AM", pref "PM", \
+    pref "LOCALE_ERAS", \
+    pref "BCE",	   pref "CE", \
+    pref "b.c.e.", pref "c.e.", \
+    pref "b.c.",   pref "a.d.", \
+    pref "LOCALE_NUMERALS", \
+}
+
+/*
+ * Structure containing the fields used in [clock format] and [clock scan]
+ */
+
+#define CLF_CTZ		(1 << 4)
+
+typedef struct TclDateFields {
+
+    /* Cacheable fields:	 */
+
+    Tcl_WideInt seconds;	/* Time expressed in seconds from the Posix
+				 * epoch */
+    Tcl_WideInt localSeconds;	/* Local time expressed in nominal seconds
+				 * from the Posix epoch */
+    int tzOffset;		/* Time zone offset in seconds east of
+				 * Greenwich */
+    Tcl_WideInt julianDay;	/* Julian Day Number in local time zone */
+    int isBce;			/* 1 if BCE */
+    int gregorian;		/* Flag == 1 if the date is Gregorian */
+    int year;			/* Year of the era */
+    int dayOfYear;		/* Day of the year (1 January == 1) */
+    int month;			/* Month number */
+    int dayOfMonth;		/* Day of the month */
+    int iso8601Year;		/* ISO8601 week-based year */
+    int iso8601Week;		/* ISO8601 week number */
+    int dayOfWeek;		/* Day of the week */
+    int hour;			/* Hours of day (in-between time only calculation) */
+    int minutes;		/* Minutes of hour (in-between time only calculation) */
+    Tcl_WideInt secondOfMin;	/* Seconds of minute (in-between time only calculation) */
+    Tcl_WideInt secondOfDay;	/* Seconds of day (in-between time only calculation) */
+
+    int flags;			/* 0 or CLF_CTZ */
+
+    /* Non cacheable fields:	 */
+
+    Tcl_Obj *tzName;		/* Name (or corresponding DST-abbreviation) of the
+				 * time zone, if set the refCount is incremented */
+} TclDateFields;
+
+#define ClockCacheableDateFieldsSize \
+    offsetof(TclDateFields, tzName)
+
+/*
+ * Meridian: am, pm, or 24-hour style.
+ */
+
+typedef enum _MERIDIAN {
+    MERam, MERpm, MER24
+} MERIDIAN;
+
+/*
+ * Structure contains return parsed fields.
+ */
+
+typedef struct DateInfo {
+    const char *dateStart;
+    const char *dateInput;
+    const char *dateEnd;
+
+    TclDateFields date;
+
+    int		flags;		/* Signals parts of date/time get found */
+    int		errFlags;	/* Signals error (part of date/time found twice) */
+
+    MERIDIAN dateMeridian;
+
+    int dateTimezone;
+    int dateDSTmode;
+
+    Tcl_WideInt dateRelMonth;
+    Tcl_WideInt dateRelDay;
+    Tcl_WideInt dateRelSeconds;
+
+    int dateMonthOrdinalIncr;
+    int dateMonthOrdinal;
+
+    int dateDayOrdinal;
+
+    Tcl_WideInt *dateRelPointer;
+
+    int dateSpaceCount;
+    int dateDigitCount;
+
+    int dateCentury;
+
+    Tcl_Obj* messages;	    /* Error messages */
+    const char* separatrix; /* String separating messages */
+} DateInfo;
+
+#define yydate	    (info->date)  /* Date fields used for converting */
+
+#define yyDay	    (info->date.dayOfMonth)
+#define yyMonth	    (info->date.month)
+#define yyYear	    (info->date.year)
+
+#define yyHour	    (info->date.hour)
+#define yyMinutes   (info->date.minutes)
+#define yySeconds   (info->date.secondOfMin)
+#define yySecondOfDay (info->date.secondOfDay)
+
+#define yyDSTmode   (info->dateDSTmode)
+#define yyDayOrdinal	(info->dateDayOrdinal)
+#define yyDayOfWeek (info->date.dayOfWeek)
+#define yyMonthOrdinalIncr  (info->dateMonthOrdinalIncr)
+#define yyMonthOrdinal	(info->dateMonthOrdinal)
+#define yyTimezone  (info->dateTimezone)
+#define yyMeridian  (info->dateMeridian)
+#define yyRelMonth  (info->dateRelMonth)
+#define yyRelDay    (info->dateRelDay)
+#define yyRelSeconds	(info->dateRelSeconds)
+#define yyRelPointer	(info->dateRelPointer)
+#define yyInput	    (info->dateInput)
+#define yyDigitCount	(info->dateDigitCount)
+#define yySpaceCount	(info->dateSpaceCount)
+
+static inline void
+ClockInitDateInfo(DateInfo *info) {
+    memset(info, 0, sizeof(DateInfo));
+}
+
+/*
+ * Structure containing the command arguments supplied to [clock format] and [clock scan]
+ */
+
+#define CLF_VALIDATE_S1	(1 << 0)
+#define CLF_VALIDATE_S2	(1 << 1)
+#define CLF_VALIDATE	(CLF_VALIDATE_S1|CLF_VALIDATE_S2)
+#define CLF_EXTENDED	(1 << 4)
+#define CLF_STRICT	(1 << 8)
+#define CLF_LOCALE_USED (1 << 15)
+
+typedef struct ClockFmtScnCmdArgs {
+    void *clientData;  /* Opaque pointer to literal pool, etc. */
+    Tcl_Interp *interp;	    /* Tcl interpreter */
+
+    Tcl_Obj *formatObj;	    /* Format */
+    Tcl_Obj *localeObj;	    /* Name of the locale where the time will be expressed. */
+    Tcl_Obj *timezoneObj;   /* Default time zone in which the time will be expressed */
+    Tcl_Obj *baseObj;	    /* Base (scan and add) or clockValue (format) */
+    int	     flags;	    /* Flags control scanning */
+
+    Tcl_Obj *mcDictObj;	    /* Current dictionary of tcl::clock package for given localeObj*/
+} ClockFmtScnCmdArgs;
+
+/* Last-period cache for fast UTC to local and backwards conversion */
+typedef struct ClockLastTZOffs {
+    /* keys */
+    Tcl_Obj    *timezoneObj;
+    int		changeover;
+    Tcl_WideInt localSeconds;
+    Tcl_WideInt rangesVal[2];   /* Bounds for cached time zone offset */
+    /* values */
+    int		tzOffset;
+    Tcl_Obj    *tzName;		/* Name (abbreviation) of this area in TZ */
+} ClockLastTZOffs;
+
+/*
+ * Structure containing the client data for [clock]
+ */
+
+typedef struct ClockClientData {
+    size_t    refCount;		/* Number of live references. */
+    Tcl_Obj **literals;		/* Pool of object literals (common, locale independent). */
+    Tcl_Obj **mcLiterals;	/* Msgcat object literals with mc-keys for search with locale. */
+    Tcl_Obj **mcLitIdxs;	/* Msgcat object indices prefixed with _IDX_,
+				 * used for quick dictionary search */
+
+    Tcl_Obj *mcDicts;		/* Msgcat collection, contains weak pointers to locale
+				 * catalogs, and owns it references (onetime referenced) */
+
+    /* Cache for current clock parameters, imparted via "configure" */
+    size_t lastTZEpoch;
+    int currentYearCentury;
+    int yearOfCenturySwitch;
+    int validMinYear;
+    int validMaxYear;
+    double maxJDN;
+
+    Tcl_Obj *systemTimeZone;
+    Tcl_Obj *systemSetupTZData;
+    Tcl_Obj *gmtSetupTimeZoneUnnorm;
+    Tcl_Obj *gmtSetupTimeZone;
+    Tcl_Obj *gmtSetupTZData;
+    Tcl_Obj *gmtTZName;
+    Tcl_Obj *lastSetupTimeZoneUnnorm;
+    Tcl_Obj *lastSetupTimeZone;
+    Tcl_Obj *lastSetupTZData;
+    Tcl_Obj *prevSetupTimeZoneUnnorm;
+    Tcl_Obj *prevSetupTimeZone;
+    Tcl_Obj *prevSetupTZData;
+
+    Tcl_Obj *defaultLocale;
+    Tcl_Obj *defaultLocaleDict;
+    Tcl_Obj *currentLocale;
+    Tcl_Obj *currentLocaleDict;
+    Tcl_Obj *lastUsedLocaleUnnorm;
+    Tcl_Obj *lastUsedLocale;
+    Tcl_Obj *lastUsedLocaleDict;
+    Tcl_Obj *prevUsedLocaleUnnorm;
+    Tcl_Obj *prevUsedLocale;
+    Tcl_Obj *prevUsedLocaleDict;
+
+    /* Cache for last base (last-second fast convert if base/tz not changed) */
+    struct {
+	Tcl_Obj *timezoneObj;
+	TclDateFields date;
+    } lastBase;
+
+    /* Last-period cache for fast UTC to Local and backwards conversion */
+    ClockLastTZOffs lastTZOffsCache[2];
+
+    int defFlags;		    /* Default flags (from configure), ATM
+				     * only CLF_VALIDATE supported */
+} ClockClientData;
+
+#define ClockDefaultYearCentury 2000
+#define ClockDefaultCenturySwitch 38
+
+/*
+ * Clock scan and format facilities.
+ */
+
+#define CLOCK_FMT_SCN_STORAGE_GC_SIZE 32
+
+#define CLOCK_MIN_TOK_CHAIN_BLOCK_SIZE 2
+
+typedef struct ClockScanToken ClockScanToken;
+
+
+typedef int ClockScanTokenProc(
+	ClockFmtScnCmdArgs *opts,
+	DateInfo *info,
+	ClockScanToken *tok);
+
+
+typedef enum _CLCKTOK_TYPE {
+   CTOKT_INT = 1, CTOKT_WIDE, CTOKT_PARSER, CTOKT_SPACE, CTOKT_WORD, CTOKT_CHAR,
+   CFMTT_PROC
+} CLCKTOK_TYPE;
+
+typedef struct ClockScanTokenMap {
+    unsigned short int	type;
+    unsigned short int	flags;
+    unsigned short int	clearFlags;
+    unsigned short int	minSize;
+    unsigned short int	maxSize;
+    unsigned short int	offs;
+    ClockScanTokenProc *parser;
+    const void	       *data;
+} ClockScanTokenMap;
+
+struct ClockScanToken {
+    ClockScanTokenMap  *map;
+    struct {
+	const char *start;
+	const char *end;
+    } tokWord;
+    unsigned short int	endDistance;
+    unsigned short int	lookAhMin;
+    unsigned short int	lookAhMax;
+    unsigned short int	lookAhTok;
+};
+
+
+#define MIN_FMT_RESULT_BLOCK_ALLOC 80
+#define MIN_FMT_RESULT_BLOCK_DELTA 0
+/* Maximal permitted threshold (buffer size > result size) in percent,
+ * to directly return the buffer without reallocate */
+#define MAX_FMT_RESULT_THRESHOLD   2
+
+typedef struct DateFormat {
+    char *resMem;
+    char *resEnd;
+    char *output;
+
+    TclDateFields date;
+
+    Tcl_Obj *localeEra;
+} DateFormat;
+
+#define CLFMT_INCR	    (1 << 3)
+#define CLFMT_DECR	    (1 << 4)
+#define CLFMT_CALC	    (1 << 5)
+#define CLFMT_LOCALE_INDX   (1 << 8)
+
+typedef struct ClockFormatToken ClockFormatToken;
+
+typedef int ClockFormatTokenProc(
+	ClockFmtScnCmdArgs *opts,
+	DateFormat *dateFmt,
+	ClockFormatToken *tok,
+	int *val);
+
+typedef struct ClockFormatTokenMap {
+    unsigned short int	type;
+    const char	       *tostr;
+    unsigned short int	width;
+    unsigned short int	flags;
+    unsigned short int	divider;
+    unsigned short int	divmod;
+    unsigned short int	offs;
+    ClockFormatTokenProc *fmtproc;
+    void	       *data;
+} ClockFormatTokenMap;
+
+struct ClockFormatToken {
+    ClockFormatTokenMap *map;
+    struct {
+	const char *start;
+	const char *end;
+    } tokWord;
+};
+
+
+typedef struct ClockFmtScnStorage ClockFmtScnStorage;
+
+struct ClockFmtScnStorage {
+    int			 objRefCount;	/* Reference count shared across threads */
+    ClockScanToken	*scnTok;
+    unsigned int	 scnTokC;
+    unsigned int	 scnSpaceCount; /* Count of mandatory spaces used in format */
+    ClockFormatToken	*fmtTok;
+    unsigned int	 fmtTokC;
+#if CLOCK_FMT_SCN_STORAGE_GC_SIZE > 0
+    ClockFmtScnStorage	*nextPtr;
+    ClockFmtScnStorage	*prevPtr;
+#endif
+    size_t		 fmtMinAlloc;
+#if 0
+   +Tcl_HashEntry    hashEntry		/* ClockFmtScnStorage is a derivate of Tcl_HashEntry,
+					 * stored by offset +sizeof(self) */
+#endif
+};
+
+/*
+ * Clock macros.
+ */
+
+/*
+ * Extracts Julian day and seconds of the day from posix seconds (tm).
+ */
+#define ClockExtractJDAndSODFromSeconds(jd, sod, tm) \
+    if (1) { \
+	jd = (tm + JULIAN_SEC_POSIX_EPOCH); \
+	if (jd >= SECONDS_PER_DAY || jd <= -SECONDS_PER_DAY) { \
+	    jd /= SECONDS_PER_DAY; \
+	    sod = (int)(tm % SECONDS_PER_DAY); \
+	} else { \
+	    sod = (int)jd, jd = 0; \
+	} \
+	if (sod < 0) { \
+	    sod += SECONDS_PER_DAY; \
+	    /* JD is affected, if switched into negative (avoid 24 hours difference) */ \
+	    if (jd <= 0) { \
+		jd--; \
+	    } \
+	} \
+    }
+
+/*
+ * Prototypes of module functions.
+ */
+
+MODULE_SCOPE int    ToSeconds(int Hours, int Minutes,
+			    int Seconds, MERIDIAN Meridian);
+MODULE_SCOPE int    IsGregorianLeapYear(TclDateFields *);
+MODULE_SCOPE void
+		    GetJulianDayFromEraYearWeekDay(
+			    TclDateFields *fields, int changeover);
+MODULE_SCOPE void
+		    GetJulianDayFromEraYearMonthDay(
+			    TclDateFields *fields, int changeover);
+MODULE_SCOPE void
+		    GetJulianDayFromEraYearDay(
+			    TclDateFields *fields, int changeover);
+MODULE_SCOPE int    ConvertUTCToLocal(void *clientData, Tcl_Interp *,
+			    TclDateFields *, Tcl_Obj *timezoneObj, int);
+MODULE_SCOPE Tcl_Obj *
+		    LookupLastTransition(Tcl_Interp *, Tcl_WideInt,
+			    Tcl_Size, Tcl_Obj *const *, Tcl_WideInt *rangesVal);
+
+MODULE_SCOPE int    TclClockFreeScan(Tcl_Interp *interp, DateInfo *info);
+
+/* tclClock.c module declarations */
+
+MODULE_SCOPE Tcl_Obj *
+		    ClockSetupTimeZone(void *clientData,
+		Tcl_Interp *interp, Tcl_Obj *timezoneObj);
+
+MODULE_SCOPE Tcl_Obj *
+		    ClockMCDict(ClockFmtScnCmdArgs *opts);
+MODULE_SCOPE Tcl_Obj *
+		    ClockMCGet(ClockFmtScnCmdArgs *opts, int mcKey);
+MODULE_SCOPE Tcl_Obj *
+		    ClockMCGetIdx(ClockFmtScnCmdArgs *opts, int mcKey);
+MODULE_SCOPE int    ClockMCSetIdx(ClockFmtScnCmdArgs *opts, int mcKey,
+			Tcl_Obj *valObj);
+
+/* tclClockFmt.c module declarations */
+
+
+MODULE_SCOPE char *
+	TclItoAw(char *buf, int val, char padchar, unsigned short int width);
+
+MODULE_SCOPE Tcl_Obj*
+		    ClockFrmObjGetLocFmtKey(Tcl_Interp *interp,
+			Tcl_Obj *objPtr);
+
+MODULE_SCOPE ClockFmtScnStorage *
+		    Tcl_GetClockFrmScnFromObj(Tcl_Interp *interp,
+			Tcl_Obj *objPtr);
+MODULE_SCOPE Tcl_Obj *
+		    ClockLocalizeFormat(ClockFmtScnCmdArgs *opts);
+
+MODULE_SCOPE int    ClockScan(DateInfo *info,
+			Tcl_Obj *strObj, ClockFmtScnCmdArgs *opts);
+
+MODULE_SCOPE int    ClockFormat(DateFormat *dateFmt,
+			ClockFmtScnCmdArgs *opts);
+
+MODULE_SCOPE void   ClockFrmScnClearCaches(void);
+
+#endif /* _TCLCLOCK_H */
diff --git a/generic/tclDictObj.c b/generic/tclDictObj.c
index 8b7bc3d..7ba981b 100644
--- a/generic/tclDictObj.c
+++ b/generic/tclDictObj.c
@@ -2074,6 +2074,60 @@ DictSizeCmd(
 /*
  *----------------------------------------------------------------------
  *
+ * TclDictObjSmartRef --
+ *
+ *	This function returns new tcl-object with the smart reference to
+ *	dictionary object.
+ *
+ *	Object returned with this function is a smart reference (pointer),
+ *	so new object of type tclDictType, that directly references given
+ *	dictionary object (with internally increased refCount).
+ *
+ *	The usage of such pointer objects allows to hold more as one
+ *	reference to the same real dictionary object, allows to make a pointer
+ *	to part of another dictionary, allows to change the dictionary without
+ *	regarding of the "shared" state of the dictionary object.
+ *
+ *	Prevents "called with shared object" exception if object is multiple
+ *	referenced.
+ *
+ * Results:
+ *	The newly create object (contains smart reference) is returned.
+ *	The returned object has a ref count of 0.
+ *
+ * Side effects:
+ *	Increases ref count of the referenced dictionary.
+ *
+ *----------------------------------------------------------------------
+ */
+
+Tcl_Obj *
+TclDictObjSmartRef(
+    Tcl_Interp *interp,
+    Tcl_Obj    *dictPtr)
+{
+    Tcl_Obj *result;
+    Dict    *dict;
+
+    if (dictPtr->typePtr != &tclDictType
+	    && SetDictFromAny(interp, dictPtr) != TCL_OK) {
+	return NULL;
+    }
+
+    DictGetInternalRep(dictPtr, dict);
+
+    result = Tcl_NewObj();
+    DictSetInternalRep(result, dict);
+    dict->refCount++;
+    result->internalRep.twoPtrValue.ptr2 = NULL;
+    result->typePtr = &tclDictType;
+
+    return result;
+}
+
+/*
+ *----------------------------------------------------------------------
+ *
  * DictExistsCmd --
  *
  *	This function implements the "dict exists" Tcl command. See the user
diff --git a/generic/tclGetDate.y b/generic/tclGetDate.y
index dc30d51..077d751 100644
--- a/generic/tclGetDate.y
+++ b/generic/tclGetDate.y
@@ -7,8 +7,9 @@
  *	only used when doing free-form date parsing, an ill-defined process
  *	anyway.
  *
- * Copyright (c) 1992-1995 Karl Lehenbauer & Mark Diekhans.
- * Copyright (c) 1995-1997 Sun Microsystems, Inc.
+ * Copyright © 1992-1995 Karl Lehenbauer & Mark Diekhans.
+ * Copyright © 1995-1997 Sun Microsystems, Inc.
+ * Copyright © 2015 Sergey G. Brester aka sebres.
  *
  * See the file "license.terms" for information on usage and redistribution of
  * this file, and for a DISCLAIMER OF ALL WARRANTIES.
@@ -27,8 +28,9 @@
  *	This file is generated from a yacc grammar defined in the file
  *	tclGetDate.y. It should not be edited directly.
  *
- * Copyright (c) 1992-1995 Karl Lehenbauer & Mark Diekhans.
- * Copyright (c) 1995-1997 Sun Microsystems, Inc.
+ * Copyright © 1992-1995 Karl Lehenbauer & Mark Diekhans.
+ * Copyright © 1995-1997 Sun Microsystems, Inc.
+ * Copyright © 2015 Sergey G. Brester aka sebres.
  *
  * See the file "license.terms" for information on usage and redistribution of
  * this file, and for a DISCLAIMER OF ALL WARRANTIES.
@@ -45,86 +47,20 @@
 #pragma warning( disable : 4102 )
 #endif /* _MSC_VER */
 
-/*
- * Meridian: am, pm, or 24-hour style.
- */
-
-typedef enum _MERIDIAN {
-    MERam, MERpm, MER24
-} MERIDIAN;
+#if 0
+#define YYDEBUG 1
+#endif
 
 /*
  * yyparse will accept a 'struct DateInfo' as its parameter; that's where the
  * parsed fields will be returned.
  */
 
-typedef struct DateInfo {
-
-    Tcl_Obj* messages;		/* Error messages */
-    const char* separatrix;	/* String separating messages */
-
-    time_t dateYear;
-    time_t dateMonth;
-    time_t dateDay;
-    int dateHaveDate;
-
-    time_t dateHour;
-    time_t dateMinutes;
-    time_t dateSeconds;
-    MERIDIAN dateMeridian;
-    int dateHaveTime;
-
-    time_t dateTimezone;
-    int dateDSTmode;
-    int dateHaveZone;
-
-    time_t dateRelMonth;
-    time_t dateRelDay;
-    time_t dateRelSeconds;
-    int dateHaveRel;
-
-    time_t dateMonthOrdinal;
-    int dateHaveOrdinalMonth;
-
-    time_t dateDayOrdinal;
-    time_t dateDayNumber;
-    int dateHaveDay;
-
-    const char *dateStart;
-    const char *dateInput;
-    time_t *dateRelPointer;
-
-    int dateDigitCount;
-} DateInfo;
+#include "tclDate.h"
 
 #define YYMALLOC	Tcl_Alloc
 #define YYFREE(x)	(Tcl_Free((void*) (x)))
 
-#define yyDSTmode	(info->dateDSTmode)
-#define yyDayOrdinal	(info->dateDayOrdinal)
-#define yyDayNumber	(info->dateDayNumber)
-#define yyMonthOrdinal	(info->dateMonthOrdinal)
-#define yyHaveDate	(info->dateHaveDate)
-#define yyHaveDay	(info->dateHaveDay)
-#define yyHaveOrdinalMonth (info->dateHaveOrdinalMonth)
-#define yyHaveRel	(info->dateHaveRel)
-#define yyHaveTime	(info->dateHaveTime)
-#define yyHaveZone	(info->dateHaveZone)
-#define yyTimezone	(info->dateTimezone)
-#define yyDay		(info->dateDay)
-#define yyMonth		(info->dateMonth)
-#define yyYear		(info->dateYear)
-#define yyHour		(info->dateHour)
-#define yyMinutes	(info->dateMinutes)
-#define yySeconds	(info->dateSeconds)
-#define yyMeridian	(info->dateMeridian)
-#define yyRelMonth	(info->dateRelMonth)
-#define yyRelDay	(info->dateRelDay)
-#define yyRelSeconds	(info->dateRelSeconds)
-#define yyRelPointer	(info->dateRelPointer)
-#define yyInput		(info->dateInput)
-#define yyDigitCount	(info->dateDigitCount)
-
 #define EPOCH		1970
 #define START_OF_TIME	1902
 #define END_OF_TIME	2037
@@ -136,18 +72,24 @@ typedef struct DateInfo {
 
 #define TM_YEAR_BASE	1900
 
-#define HOUR(x)		((int) (60 * (x)))
-#define SECSPERDAY	(24L * 60L * 60L)
+#define HOUR(x)		((60 * (int)(x)))
 #define IsLeapYear(x)	(((x) % 4 == 0) && ((x) % 100 != 0 || (x) % 400 == 0))
 
+#define yyIncrFlags(f)				\
+    do {					\
+	info->errFlags |= (info->flags & (f));	\
+	if (info->errFlags) { YYABORT; }	\
+	info->flags |= (f);			\
+    } while (0);
+
 /*
  * An entry in the lexical lookup table.
  */
 
-typedef struct _TABLE {
+typedef struct {
     const char *name;
     int type;
-    time_t value;
+    int value;
 } TABLE;
 
 /*
@@ -161,7 +103,7 @@ typedef enum _DSTMODE {
 %}
 
 %union {
-    time_t Number;
+    long long Number;
     enum _MERIDIAN Meridian;
 }
 
@@ -172,12 +114,10 @@ typedef enum _DSTMODE {
  */
 
 static int		LookupWord(YYSTYPE* yylvalPtr, char *buff);
- static void		TclDateerror(YYLTYPE* location,
+static void		TclDateerror(YYLTYPE* location,
 				     DateInfo* info, const char *s);
- static int		TclDatelex(YYSTYPE* yylvalPtr, YYLTYPE* location,
+static int		TclDatelex(YYSTYPE* yylvalPtr, YYLTYPE* location,
 				   DateInfo* info);
-static time_t		ToSeconds(time_t Hours, time_t Minutes,
-			    time_t Seconds, MERIDIAN Meridian);
 MODULE_SCOPE int	yyparse(DateInfo*);
 
 %}
@@ -191,14 +131,18 @@ MODULE_SCOPE int	yyparse(DateInfo*);
 %token	tMONTH_UNIT
 %token	tSTARDATE
 %token	tSEC_UNIT
-%token	tSNUMBER
 %token	tUNUMBER
 %token	tZONE
+%token	tZONEwO4
+%token	tZONEwO2
 %token	tEPOCH
 %token	tDST
-%token	tISOBASE
+%token	tISOBAS8
+%token	tISOBAS6
+%token	tISOBASL
 %token	tDAY_UNIT
 %token	tNEXT
+%token	SP
 
 %type	<Number>	tDAY
 %type	<Number>	tDAYZONE
@@ -206,10 +150,14 @@ MODULE_SCOPE int	yyparse(DateInfo*);
 %type	<Number>	tMONTH_UNIT
 %type	<Number>	tDST
 %type	<Number>	tSEC_UNIT
-%type	<Number>	tSNUMBER
 %type	<Number>	tUNUMBER
+%type	<Number>	INTNUM
 %type	<Number>	tZONE
-%type	<Number>	tISOBASE
+%type	<Number>	tZONEwO4
+%type	<Number>	tZONEwO2
+%type	<Number>	tISOBAS8
+%type	<Number>	tISOBAS6
+%type	<Number>	tISOBASL
 %type	<Number>	tDAY_UNIT
 %type	<Number>	unit
 %type	<Number>	sign
@@ -222,100 +170,121 @@ MODULE_SCOPE int	yyparse(DateInfo*);
 
 spec	: /* NULL */
 	| spec item
+	/* | spec SP item */
 	;
 
 item	: time {
-	    yyHaveTime++;
+	    yyIncrFlags(CLF_TIME);
 	}
 	| zone {
-	    yyHaveZone++;
+	    yyIncrFlags(CLF_ZONE);
 	}
 	| date {
-	    yyHaveDate++;
+	    yyIncrFlags(CLF_HAVEDATE);
 	}
 	| ordMonth {
-	    yyHaveOrdinalMonth++;
+	    yyIncrFlags(CLF_ORDINALMONTH);
 	}
 	| day {
-	    yyHaveDay++;
+	    yyIncrFlags(CLF_DAYOFWEEK);
 	}
 	| relspec {
-	    yyHaveRel++;
+	    info->flags |= CLF_RELCONV;
 	}
 	| iso {
-	    yyHaveTime++;
-	    yyHaveDate++;
+	    yyIncrFlags(CLF_TIME|CLF_HAVEDATE);
 	}
 	| trek {
-	    yyHaveTime++;
-	    yyHaveDate++;
-	    yyHaveRel++;
+	    yyIncrFlags(CLF_TIME|CLF_HAVEDATE);
+	    info->flags |= CLF_RELCONV;
 	}
-	| number
+	| numitem
 	;
 
-time	: tUNUMBER tMERIDIAN {
+iextime : tUNUMBER ':' tUNUMBER ':' tUNUMBER {
 	    yyHour = $1;
-	    yyMinutes = 0;
-	    yySeconds = 0;
-	    yyMeridian = $2;
+	    yyMinutes = $3;
+	    yySeconds = $5;
 	}
-	| tUNUMBER ':' tUNUMBER o_merid {
+	| tUNUMBER ':' tUNUMBER {
 	    yyHour = $1;
 	    yyMinutes = $3;
 	    yySeconds = 0;
-	    yyMeridian = $4;
 	}
-	| tUNUMBER ':' tUNUMBER ':' tUNUMBER o_merid {
+	;
+time	: tUNUMBER tMERIDIAN {
 	    yyHour = $1;
-	    yyMinutes = $3;
-	    yySeconds = $5;
-	    yyMeridian = $6;
+	    yyMinutes = 0;
+	    yySeconds = 0;
+	    yyMeridian = $2;
+	}
+	| iextime o_merid {
+	    yyMeridian = $2;
 	}
 	;
 
 zone	: tZONE tDST {
 	    yyTimezone = $1;
-	    if (yyTimezone > HOUR( 12)) yyTimezone -= HOUR(100);
 	    yyDSTmode = DSTon;
 	}
 	| tZONE {
 	    yyTimezone = $1;
-	    if (yyTimezone > HOUR( 12)) yyTimezone -= HOUR(100);
 	    yyDSTmode = DSToff;
 	}
 	| tDAYZONE {
 	    yyTimezone = $1;
 	    yyDSTmode = DSTon;
 	}
-	| sign tUNUMBER {
+	| tZONEwO4 sign INTNUM { /* GMT+0100, GMT-1000, etc. */
+	    yyTimezone = $1 - $2*($3 % 100 + ($3 / 100) * 60);
+	    yyDSTmode = DSToff;
+	}
+	| tZONEwO2 sign INTNUM { /* GMT+1, GMT-10, etc. */
+	    yyTimezone = $1 - $2*($3 * 60);
+	    yyDSTmode = DSToff;
+	}
+	| sign INTNUM { /* +0100, -0100 */
 	    yyTimezone = -$1*($2 % 100 + ($2 / 100) * 60);
 	    yyDSTmode = DSToff;
 	}
 	;
 
+comma	: ','
+	| ',' SP
+	;
+
 day	: tDAY {
 	    yyDayOrdinal = 1;
-	    yyDayNumber = $1;
+	    yyDayOfWeek = $1;
 	}
-	| tDAY ',' {
+	| tDAY comma {
 	    yyDayOrdinal = 1;
-	    yyDayNumber = $1;
+	    yyDayOfWeek = $1;
 	}
 	| tUNUMBER tDAY {
 	    yyDayOrdinal = $1;
-	    yyDayNumber = $2;
+	    yyDayOfWeek = $2;
+	}
+	| sign SP tUNUMBER tDAY {
+	    yyDayOrdinal = $1 * $3;
+	    yyDayOfWeek = $4;
 	}
 	| sign tUNUMBER tDAY {
 	    yyDayOrdinal = $1 * $2;
-	    yyDayNumber = $3;
+	    yyDayOfWeek = $3;
 	}
 	| tNEXT tDAY {
 	    yyDayOrdinal = 2;
-	    yyDayNumber = $2;
+	    yyDayOfWeek = $2;
 	}
 	;
 
+iexdate	: tUNUMBER '-' tUNUMBER '-' tUNUMBER {
+	    yyMonth = $3;
+	    yyDay = $5;
+	    yyYear = $1;
+	}
+	;
 date	: tUNUMBER '/' tUNUMBER {
 	    yyMonth = $1;
 	    yyDay = $3;
@@ -325,26 +294,17 @@ date	: tUNUMBER '/' tUNUMBER {
 	    yyDay = $3;
 	    yyYear = $5;
 	}
-	| tISOBASE {
-	    yyYear = $1 / 10000;
-	    yyMonth = ($1 % 10000)/100;
-	    yyDay = $1 % 100;
-	}
+	| isodate
 	| tUNUMBER '-' tMONTH '-' tUNUMBER {
 	    yyDay = $1;
 	    yyMonth = $3;
 	    yyYear = $5;
 	}
-	| tUNUMBER '-' tUNUMBER '-' tUNUMBER {
-	    yyMonth = $3;
-	    yyDay = $5;
-	    yyYear = $1;
-	}
 	| tMONTH tUNUMBER {
 	    yyMonth = $1;
 	    yyDay = $2;
 	}
-	| tMONTH tUNUMBER ',' tUNUMBER {
+	| tMONTH tUNUMBER comma tUNUMBER {
 	    yyMonth = $1;
 	    yyDay = $2;
 	    yyYear = $4;
@@ -366,44 +326,38 @@ date	: tUNUMBER '/' tUNUMBER {
 	;
 
 ordMonth: tNEXT tMONTH {
-	    yyMonthOrdinal = 1;
-	    yyMonth = $2;
+	    yyMonthOrdinalIncr = 1;
+	    yyMonthOrdinal = $2;
 	}
 	| tNEXT tUNUMBER tMONTH {
-	    yyMonthOrdinal = $2;
-	    yyMonth = $3;
+	    yyMonthOrdinalIncr = $2;
+	    yyMonthOrdinal = $3;
 	}
 	;
 
-iso	: tUNUMBER '-' tUNUMBER '-' tUNUMBER tZONE
-		tUNUMBER ':' tUNUMBER ':' tUNUMBER {
-	    if ($6 != HOUR( 7) + HOUR(100)) YYABORT;
-	    yyYear = $1;
-	    yyMonth = $3;
-	    yyDay = $5;
-	    yyHour = $7;
-	    yyMinutes = $9;
-	    yySeconds = $11;
-	}
-	| tISOBASE tZONE tISOBASE {
-	    if ($2 != HOUR( 7) + HOUR(100)) YYABORT;
+isosep	: 'T'|SP
+	;
+isodate	: tISOBAS8 { /* YYYYMMDD */
 	    yyYear = $1 / 10000;
 	    yyMonth = ($1 % 10000)/100;
 	    yyDay = $1 % 100;
-	    yyHour = $3 / 10000;
-	    yyMinutes = ($3 % 10000)/100;
-	    yySeconds = $3 % 100;
 	}
-	| tISOBASE tZONE tUNUMBER ':' tUNUMBER ':' tUNUMBER {
-	    if ($2 != HOUR( 7) + HOUR(100)) YYABORT;
+	| tISOBAS6 { /* YYMMDD */
 	    yyYear = $1 / 10000;
 	    yyMonth = ($1 % 10000)/100;
 	    yyDay = $1 % 100;
-	    yyHour = $3;
-	    yyMinutes = $5;
-	    yySeconds = $7;
 	}
-	| tISOBASE tISOBASE {
+	| iexdate
+	;
+isotime	: tISOBAS6 {
+	    yyHour = $1 / 10000;
+	    yyMinutes = ($1 % 10000)/100;
+	    yySeconds = $1 % 100;
+	}
+	| iextime
+	;
+iso	: isodate isosep isotime
+	| tISOBASL tISOBAS6 { /* YYYYMMDDhhmmss */
 	    yyYear = $1 / 10000;
 	    yyMonth = ($1 % 10000)/100;
 	    yyDay = $1 % 100;
@@ -411,9 +365,18 @@ iso	: tUNUMBER '-' tUNUMBER '-' tUNUMBER tZONE
 	    yyMinutes = ($2 % 10000)/100;
 	    yySeconds = $2 % 100;
 	}
+	| tISOBASL tUNUMBER { /* YYYYMMDDhhmm */
+	    if (yyDigitCount != 4) YYABORT; /* normally unreached */
+	    yyYear = $1 / 10000;
+	    yyMonth = ($1 % 10000)/100;
+	    yyDay = $1 % 100;
+	    yyHour = $2 / 100;
+	    yyMinutes = ($2 % 100);
+	    yySeconds = 0;
+	}
 	;
 
-trek	: tSTARDATE tUNUMBER '.' tUNUMBER {
+trek	: tSTARDATE INTNUM '.' tUNUMBER {
 	    /*
 	     * Offset computed year by -377 so that the returned years will be
 	     * in a range accessible with a 32 bit clock seconds value.
@@ -423,7 +386,7 @@ trek	: tSTARDATE tUNUMBER '.' tUNUMBER {
 	    yyDay  = 1;
 	    yyMonth = 1;
 	    yyRelDay += (($2%1000)*(365 + IsLeapYear(yyYear)))/1000;
-	    yyRelSeconds += $4 * 144 * 60;
+	    yyRelSeconds += $4 * (144LL * 60LL);
 	}
 	;
 
@@ -435,16 +398,19 @@ relspec : relunits tAGO {
 	| relunits
 	;
 
-relunits : sign tUNUMBER unit {
+relunits : sign SP INTNUM unit {
+	    *yyRelPointer += $1 * $3 * $4;
+	}
+	| sign INTNUM unit {
 	    *yyRelPointer += $1 * $2 * $3;
 	}
-	| tUNUMBER unit {
+	| INTNUM unit {
 	    *yyRelPointer += $1 * $2;
 	}
 	| tNEXT unit {
 	    *yyRelPointer += $2;
 	}
-	| tNEXT tUNUMBER unit {
+	| tNEXT INTNUM unit {
 	    *yyRelPointer += $2 * $3;
 	}
 	| unit {
@@ -474,11 +440,22 @@ unit	: tSEC_UNIT {
 	}
 	;
 
-number	: tUNUMBER {
-	    if (yyHaveTime && yyHaveDate && !yyHaveRel) {
+INTNUM	: tUNUMBER {
+	    $$ = $1;
+	}
+	| tISOBAS6 {
+	    $$ = $1;
+	}
+	| tISOBAS8 {
+	    $$ = $1;
+	}
+	;
+
+numitem	: tUNUMBER {
+	    if ((info->flags & (CLF_TIME|CLF_HAVEDATE|CLF_RELCONV)) == (CLF_TIME|CLF_HAVEDATE)) {
 		yyYear = $1;
 	    } else {
-		yyHaveTime++;
+		yyIncrFlags(CLF_TIME);
 		if (yyDigitCount <= 2) {
 		    yyHour = $1;
 		    yyMinutes = 0;
@@ -563,20 +540,6 @@ static const TABLE OtherTable[] = {
     { "last",		tUNUMBER,	-1 },
     { "this",		tSEC_UNIT,	0 },
     { "next",		tNEXT,		1 },
-#if 0
-    { "first",		tUNUMBER,	1 },
-    { "second",		tUNUMBER,	2 },
-    { "third",		tUNUMBER,	3 },
-    { "fourth",		tUNUMBER,	4 },
-    { "fifth",		tUNUMBER,	5 },
-    { "sixth",		tUNUMBER,	6 },
-    { "seventh",	tUNUMBER,	7 },
-    { "eighth",		tUNUMBER,	8 },
-    { "ninth",		tUNUMBER,	9 },
-    { "tenth",		tUNUMBER,	10 },
-    { "eleventh",	tUNUMBER,	11 },
-    { "twelfth",	tUNUMBER,	12 },
-#endif
     { "ago",		tAGO,		1 },
     { "epoch",		tEPOCH,		0 },
     { "stardate",	tSTARDATE,	0 },
@@ -676,34 +639,44 @@ static const TABLE TimezoneTable[] = {
  */
 
 static const TABLE MilitaryTable[] = {
-    { "a",	tZONE,	-HOUR( 1) + HOUR(100) },
-    { "b",	tZONE,	-HOUR( 2) + HOUR(100) },
-    { "c",	tZONE,	-HOUR( 3) + HOUR(100) },
-    { "d",	tZONE,	-HOUR( 4) + HOUR(100) },
-    { "e",	tZONE,	-HOUR( 5) + HOUR(100) },
-    { "f",	tZONE,	-HOUR( 6) + HOUR(100) },
-    { "g",	tZONE,	-HOUR( 7) + HOUR(100) },
-    { "h",	tZONE,	-HOUR( 8) + HOUR(100) },
-    { "i",	tZONE,	-HOUR( 9) + HOUR(100) },
-    { "k",	tZONE,	-HOUR(10) + HOUR(100) },
-    { "l",	tZONE,	-HOUR(11) + HOUR(100) },
-    { "m",	tZONE,	-HOUR(12) + HOUR(100) },
-    { "n",	tZONE,	HOUR(  1) + HOUR(100) },
-    { "o",	tZONE,	HOUR(  2) + HOUR(100) },
-    { "p",	tZONE,	HOUR(  3) + HOUR(100) },
-    { "q",	tZONE,	HOUR(  4) + HOUR(100) },
-    { "r",	tZONE,	HOUR(  5) + HOUR(100) },
-    { "s",	tZONE,	HOUR(  6) + HOUR(100) },
-    { "t",	tZONE,	HOUR(  7) + HOUR(100) },
-    { "u",	tZONE,	HOUR(  8) + HOUR(100) },
-    { "v",	tZONE,	HOUR(  9) + HOUR(100) },
-    { "w",	tZONE,	HOUR( 10) + HOUR(100) },
-    { "x",	tZONE,	HOUR( 11) + HOUR(100) },
-    { "y",	tZONE,	HOUR( 12) + HOUR(100) },
-    { "z",	tZONE,	HOUR( 0)  + HOUR(100) },
+    { "a",	tZONE,	-HOUR( 1) },
+    { "b",	tZONE,	-HOUR( 2) },
+    { "c",	tZONE,	-HOUR( 3) },
+    { "d",	tZONE,	-HOUR( 4) },
+    { "e",	tZONE,	-HOUR( 5) },
+    { "f",	tZONE,	-HOUR( 6) },
+    { "g",	tZONE,	-HOUR( 7) },
+    { "h",	tZONE,	-HOUR( 8) },
+    { "i",	tZONE,	-HOUR( 9) },
+    { "k",	tZONE,	-HOUR(10) },
+    { "l",	tZONE,	-HOUR(11) },
+    { "m",	tZONE,	-HOUR(12) },
+    { "n",	tZONE,	HOUR(  1) },
+    { "o",	tZONE,	HOUR(  2) },
+    { "p",	tZONE,	HOUR(  3) },
+    { "q",	tZONE,	HOUR(  4) },
+    { "r",	tZONE,	HOUR(  5) },
+    { "s",	tZONE,	HOUR(  6) },
+    { "t",	tZONE,	HOUR(  7) },
+    { "u",	tZONE,	HOUR(  8) },
+    { "v",	tZONE,	HOUR(  9) },
+    { "w",	tZONE,	HOUR( 10) },
+    { "x",	tZONE,	HOUR( 11) },
+    { "y",	tZONE,	HOUR( 12) },
+    { "z",	tZONE,	HOUR( 0) },
     { NULL, 0, 0 }
 };
 
+static inline const char *
+bypassSpaces(
+    const char *s)
+{
+    while (TclIsSpaceProc(*s)) {
+	s++;
+    }
+    return s;
+}
+
 /*
  * Dump error messages in the bit bucket.
  */
@@ -715,6 +688,9 @@ TclDateerror(
     const char *s)
 {
     Tcl_Obj* t;
+    if (!infoPtr->messages) {
+	TclNewObj(infoPtr->messages);
+    }
     Tcl_AppendToObj(infoPtr->messages, infoPtr->separatrix, -1);
     Tcl_AppendToObj(infoPtr->messages, s, -1);
     Tcl_AppendToObj(infoPtr->messages, " (characters ", -1);
@@ -731,11 +707,11 @@ TclDateerror(
     infoPtr->separatrix = "\n";
 }
 
-static time_t
+int
 ToSeconds(
-    time_t Hours,
-    time_t Minutes,
-    time_t Seconds,
+    int Hours,
+    int Minutes,
+    int Seconds,
     MERIDIAN Meridian)
 {
     if (Minutes < 0 || Minutes > 59 || Seconds < 0 || Seconds > 59) {
@@ -746,17 +722,17 @@ ToSeconds(
 	if (Hours < 0 || Hours > 23) {
 	    return -1;
 	}
-	return (Hours * 60L + Minutes) * 60L + Seconds;
+	return (Hours * 60 + Minutes) * 60 + Seconds;
     case MERam:
 	if (Hours < 1 || Hours > 12) {
 	    return -1;
 	}
-	return ((Hours % 12) * 60L + Minutes) * 60L + Seconds;
+	return ((Hours % 12) * 60 + Minutes) * 60 + Seconds;
     case MERpm:
 	if (Hours < 1 || Hours > 12) {
 	    return -1;
 	}
-	return (((Hours % 12) + 12) * 60L + Minutes) * 60L + Seconds;
+	return (((Hours % 12) + 12) * 60 + Minutes) * 60 + Seconds;
     }
     return -1;			/* Should never be reached */
 }
@@ -777,11 +753,11 @@ LookupWord(
 
     Tcl_UtfToLower(buff);
 
-    if (strcmp(buff, "am") == 0 || strcmp(buff, "a.m.") == 0) {
+    if (*buff == 'a' && (strcmp(buff, "am") == 0 || strcmp(buff, "a.m.") == 0)) {
 	yylvalPtr->Meridian = MERam;
 	return tMERIDIAN;
     }
-    if (strcmp(buff, "pm") == 0 || strcmp(buff, "p.m.") == 0) {
+    if (*buff == 'p' && (strcmp(buff, "pm") == 0 || strcmp(buff, "p.m.") == 0)) {
 	yylvalPtr->Meridian = MERpm;
 	return tMERIDIAN;
     }
@@ -895,50 +871,114 @@ TclDatelex(
     char *p;
     char buff[20];
     int Count;
+    const char *tokStart;
 
     location->first_column = yyInput - info->dateStart;
     for ( ; ; ) {
-	while (TclIsSpaceProcM(*yyInput)) {
-	    yyInput++;
+
+	if (isspace(UCHAR(*yyInput))) {
+	    yyInput = bypassSpaces(yyInput);
+	    /* ignore space at end of text and before some words */
+	    c = *yyInput;
+	    if (c != '\0' && !isalpha(UCHAR(c))) {
+		return SP;
+	    }
 	}
+	tokStart = yyInput;
 
 	if (isdigit(UCHAR(c = *yyInput))) { /* INTL: digit */
+
 	    /*
 	     * Convert the string into a number; count the number of digits.
 	     */
-
-	    Count = 0;
-	    for (yylvalPtr->Number = 0;
-		    isdigit(UCHAR(c = *yyInput++)); ) {	  /* INTL: digit */
-		yylvalPtr->Number = 10 * yylvalPtr->Number + c - '0';
-		Count++;
+	    long long num = c - '0';
+	    p = (char *)yyInput;
+	    while (isdigit(UCHAR(c = *(++p)))) {
+		if (num >= 0) {
+		    num *= 10; num += c - '0';
+		}
 	    }
-	    yyInput--;
-	    yyDigitCount = Count;
+	    yylvalPtr->Number = num;
+	    yyDigitCount = p - yyInput;
+	    yyInput = p;
 
 	    /*
 	     * A number with 6 or more digits is considered an ISO 8601 base.
 	     */
 
-	    if (Count >= 6) {
-		location->last_column = yyInput - info->dateStart - 1;
-		return tISOBASE;
-	    } else {
-		location->last_column = yyInput - info->dateStart - 1;
-		return tUNUMBER;
+	    location->last_column = yyInput - info->dateStart - 1;
+	    if (yyDigitCount >= 6) {
+		if (yyDigitCount == 14 || yyDigitCount == 12) {
+		    /* long form of ISO 8601 (without separator), either
+		     * YYYYMMDDhhmmss or YYYYMMDDhhmm, so reduce to date
+		     * (8 chars is isodate) */
+		    p = (char *)tokStart;
+		    num = *p++ - '0';
+		    do {
+			num *= 10; num += *p++ - '0';
+		    } while (p - tokStart < 8);
+		    yylvalPtr->Number = num;
+		    yyDigitCount = 8;
+		    yyInput = p;
+		    location->last_column = yyInput - info->dateStart - 1;
+		    return tISOBASL;
+		}
+		if (yyDigitCount > 14) { /* overflow */
+		    return tID;
+		}
+		if (yyDigitCount == 8) {
+		    return tISOBAS8;
+		}
+		if (yyDigitCount == 6) {
+		    return tISOBAS6;
+		}
 	    }
+	    /* ignore spaces after digits (optional) */
+	    yyInput = bypassSpaces(yyInput);
+	    return tUNUMBER;
 	}
 	if (!(c & 0x80) && isalpha(UCHAR(c))) {		  /* INTL: ISO only. */
+	    int ret;
 	    for (p = buff; isalpha(UCHAR(c = *yyInput++)) /* INTL: ISO only. */
 		     || c == '.'; ) {
-		if (p < &buff[sizeof buff - 1]) {
+		if (p < &buff[sizeof(buff) - 1]) {
 		    *p++ = c;
 		}
 	    }
 	    *p = '\0';
 	    yyInput--;
 	    location->last_column = yyInput - info->dateStart - 1;
-	    return LookupWord(yylvalPtr, buff);
+	    ret = LookupWord(yylvalPtr, buff);
+	    /*
+	     * lookahead:
+	     *	for spaces to consider word boundaries (for instance
+	     *	literal T in isodateTisotimeZ is not a TZ, but Z is UTC);
+	     *	for +/- digit, to differentiate between "GMT+1000 day" and "GMT +1000 day";
+	     * bypass spaces after token (but ignore by TZ+OFFS), because should
+	     * recognize next SP token, if TZ only.
+	     */
+	    if (ret == tZONE || ret == tDAYZONE) {
+		c = *yyInput;
+		if (isdigit(UCHAR(c))) { /* literal not a TZ  */
+		    yyInput = tokStart;
+		    return *yyInput++;
+		}
+		if ((c == '+' || c == '-') && isdigit(UCHAR(*(yyInput+1)))) {
+		    if ( !isdigit(UCHAR(*(yyInput+2)))
+		      || !isdigit(UCHAR(*(yyInput+3)))) {
+			/* GMT+1, GMT-10, etc. */
+			return tZONEwO2;
+		    }
+		    if ( isdigit(UCHAR(*(yyInput+4)))
+		      && !isdigit(UCHAR(*(yyInput+5)))) {
+			/* GMT+1000, etc. */
+			return tZONEwO4;
+		    }
+		}
+	    }
+	    yyInput = bypassSpaces(yyInput);
+	    return ret;
+
 	}
 	if (c != '(') {
 	    location->last_column = yyInput - info->dateStart;
@@ -958,169 +998,75 @@ TclDatelex(
 	} while (Count > 0);
     }
 }
-
+
 int
-TclClockOldscanObjCmd(
-    TCL_UNUSED(void *),
+TclClockFreeScan(
     Tcl_Interp *interp,		/* Tcl interpreter */
-    int objc,			/* Count of parameters */
-    Tcl_Obj *const *objv)	/* Parameters */
+    DateInfo *info)		/* Input and result parameters */
 {
-    Tcl_Obj *result, *resultElement;
-    int yr, mo, da;
-    DateInfo dateInfo;
-    DateInfo* info = &dateInfo;
     int status;
 
-    if (objc != 5) {
-	Tcl_WrongNumArgs(interp, 1, objv,
-		"stringToParse baseYear baseMonth baseDay" );
-	return TCL_ERROR;
-    }
+  #if YYDEBUG
+    /* enable debugging if compiled with YYDEBUG */
+    yydebug = 1;
+  #endif
 
-    yyInput = TclGetString(objv[1]);
-    dateInfo.dateStart = yyInput;
-
-    yyHaveDate = 0;
-    if (Tcl_GetIntFromObj(interp, objv[2], &yr) != TCL_OK
-	    || Tcl_GetIntFromObj(interp, objv[3], &mo) != TCL_OK
-	    || Tcl_GetIntFromObj(interp, objv[4], &da) != TCL_OK) {
-	return TCL_ERROR;
-    }
-    yyYear = yr; yyMonth = mo; yyDay = da;
-
-    yyHaveTime = 0;
-    yyHour = 0; yyMinutes = 0; yySeconds = 0; yyMeridian = MER24;
-
-    yyHaveZone = 0;
-    yyTimezone = 0; yyDSTmode = DSTmaybe;
+    /*
+     * yyInput = stringToParse;
+     *
+     * ClockInitDateInfo(info) should be executed to pre-init info;
+     */
 
-    yyHaveOrdinalMonth = 0;
-    yyMonthOrdinal = 0;
+    yyDSTmode = DSTmaybe;
 
-    yyHaveDay = 0;
-    yyDayOrdinal = 0; yyDayNumber = 0;
+    info->separatrix = "";
 
-    yyHaveRel = 0;
-    yyRelMonth = 0; yyRelDay = 0; yyRelSeconds = 0; yyRelPointer = NULL;
+    info->dateStart = yyInput;
 
-    TclNewObj(dateInfo.messages);
-    dateInfo.separatrix = "";
-    Tcl_IncrRefCount(dateInfo.messages);
+    /* ignore spaces at begin */
+    yyInput = bypassSpaces(yyInput);
 
-    status = yyparse(&dateInfo);
+    /* parse */
+    status = yyparse(info);
     if (status == 1) {
-	Tcl_SetObjResult(interp, dateInfo.messages);
-	Tcl_DecrRefCount(dateInfo.messages);
-	Tcl_SetErrorCode(interp, "TCL", "VALUE", "DATE", "PARSE", (char *)NULL);
-	return TCL_ERROR;
+    	const char *msg = NULL;
+	if (info->errFlags & CLF_HAVEDATE) {
+	    msg = "more than one date in string";
+	} else if (info->errFlags & CLF_TIME) {
+	    msg = "more than one time of day in string";
+	} else if (info->errFlags & CLF_ZONE) {
+	    msg = "more than one time zone in string";
+	} else if (info->errFlags & CLF_DAYOFWEEK) {
+	    msg = "more than one weekday in string";
+	} else if (info->errFlags & CLF_ORDINALMONTH) {
+	    msg = "more than one ordinal month in string";
+	}
+	if (msg) {
+	    Tcl_SetObjResult(interp, Tcl_NewStringObj(msg, -1));
+	    Tcl_SetErrorCode(interp, "TCL", "VALUE", "DATE", "MULTIPLE", (char *)NULL);
+	} else {
+	    Tcl_SetObjResult(interp,
+		info->messages ? info->messages : Tcl_NewObj());
+	    info->messages = NULL;
+	    Tcl_SetErrorCode(interp, "TCL", "VALUE", "DATE", "PARSE", (char *)NULL);
+	}
+	status = TCL_ERROR;
     } else if (status == 2) {
 	Tcl_SetObjResult(interp, Tcl_NewStringObj("memory exhausted", -1));
-	Tcl_DecrRefCount(dateInfo.messages);
 	Tcl_SetErrorCode(interp, "TCL", "MEMORY", (char *)NULL);
-	return TCL_ERROR;
+	status = TCL_ERROR;
     } else if (status != 0) {
 	Tcl_SetObjResult(interp, Tcl_NewStringObj("Unknown status returned "
 						  "from date parser. Please "
 						  "report this error as a "
 						  "bug in Tcl.", -1));
-	Tcl_DecrRefCount(dateInfo.messages);
 	Tcl_SetErrorCode(interp, "TCL", "BUG", (char *)NULL);
-	return TCL_ERROR;
+	status = TCL_ERROR;
     }
-    Tcl_DecrRefCount(dateInfo.messages);
-
-    if (yyHaveDate > 1) {
-	Tcl_SetObjResult(interp,
-		Tcl_NewStringObj("more than one date in string", -1));
-	Tcl_SetErrorCode(interp, "TCL", "VALUE", "DATE", "MULTIPLE", (char *)NULL);
-	return TCL_ERROR;
-    }
-    if (yyHaveTime > 1) {
-	Tcl_SetObjResult(interp,
-		Tcl_NewStringObj("more than one time of day in string", -1));
-	Tcl_SetErrorCode(interp, "TCL", "VALUE", "DATE", "MULTIPLE", (char *)NULL);
-	return TCL_ERROR;
-    }
-    if (yyHaveZone > 1) {
-	Tcl_SetObjResult(interp,
-		Tcl_NewStringObj("more than one time zone in string", -1));
-	Tcl_SetErrorCode(interp, "TCL", "VALUE", "DATE", "MULTIPLE", (char *)NULL);
-	return TCL_ERROR;
-    }
-    if (yyHaveDay > 1) {
-	Tcl_SetObjResult(interp,
-		Tcl_NewStringObj("more than one weekday in string", -1));
-	Tcl_SetErrorCode(interp, "TCL", "VALUE", "DATE", "MULTIPLE", (char *)NULL);
-	return TCL_ERROR;
-    }
-    if (yyHaveOrdinalMonth > 1) {
-	Tcl_SetObjResult(interp,
-		Tcl_NewStringObj("more than one ordinal month in string", -1));
-	Tcl_SetErrorCode(interp, "TCL", "VALUE", "DATE", "MULTIPLE", (char *)NULL);
-	return TCL_ERROR;
-    }
-
-    TclNewObj(result);
-    TclNewObj(resultElement);
-    if (yyHaveDate) {
-	Tcl_ListObjAppendElement(interp, resultElement,
-		Tcl_NewIntObj(yyYear));
-	Tcl_ListObjAppendElement(interp, resultElement,
-		Tcl_NewIntObj(yyMonth));
-	Tcl_ListObjAppendElement(interp, resultElement,
-		Tcl_NewIntObj(yyDay));
-    }
-    Tcl_ListObjAppendElement(interp, result, resultElement);
-
-    if (yyHaveTime) {
-	Tcl_ListObjAppendElement(interp, result, Tcl_NewIntObj(
-		ToSeconds(yyHour, yyMinutes, yySeconds, (MERIDIAN)yyMeridian)));
-    } else {
-	TclNewObj(resultElement);
-	Tcl_ListObjAppendElement(interp, result, resultElement);
-    }
-
-    TclNewObj(resultElement);
-    if (yyHaveZone) {
-	Tcl_ListObjAppendElement(interp, resultElement,
-		Tcl_NewIntObj(-yyTimezone));
-	Tcl_ListObjAppendElement(interp, resultElement,
-		Tcl_NewIntObj(1 - yyDSTmode));
+    if (info->messages) {
+	Tcl_DecrRefCount(info->messages);
     }
-    Tcl_ListObjAppendElement(interp, result, resultElement);
-
-    TclNewObj(resultElement);
-    if (yyHaveRel) {
-	Tcl_ListObjAppendElement(interp, resultElement,
-		Tcl_NewIntObj(yyRelMonth));
-	Tcl_ListObjAppendElement(interp, resultElement,
-		Tcl_NewIntObj(yyRelDay));
-	Tcl_ListObjAppendElement(interp, resultElement,
-		Tcl_NewIntObj(yyRelSeconds));
-    }
-    Tcl_ListObjAppendElement(interp, result, resultElement);
-
-    TclNewObj(resultElement);
-    if (yyHaveDay && !yyHaveDate) {
-	Tcl_ListObjAppendElement(interp, resultElement,
-		Tcl_NewIntObj(yyDayOrdinal));
-	Tcl_ListObjAppendElement(interp, resultElement,
-		Tcl_NewIntObj(yyDayNumber));
-    }
-    Tcl_ListObjAppendElement(interp, result, resultElement);
-
-    TclNewObj(resultElement);
-    if (yyHaveOrdinalMonth) {
-	Tcl_ListObjAppendElement(interp, resultElement,
-		Tcl_NewIntObj(yyMonthOrdinal));
-	Tcl_ListObjAppendElement(interp, resultElement,
-		Tcl_NewIntObj(yyMonth));
-    }
-    Tcl_ListObjAppendElement(interp, result, resultElement);
-
-    Tcl_SetObjResult(interp, result);
-    return TCL_OK;
+    return status;
 }
 
 /*
diff --git a/generic/tclInt.h b/generic/tclInt.h
index ada17b3..3241651 100644
--- a/generic/tclInt.h
+++ b/generic/tclInt.h
@@ -3288,6 +3288,7 @@ MODULE_SCOPE int	TclFindDictElement(Tcl_Interp *interp,
 			    const char *dict, Tcl_Size dictLength,
 			    const char **elementPtr, const char **nextPtr,
 			    Tcl_Size *sizePtr, int *literalPtr);
+MODULE_SCOPE Tcl_Obj *	TclDictObjSmartRef(Tcl_Interp *interp, Tcl_Obj *);
 /* TIP #280 - Modified token based evaluation, with line information. */
 MODULE_SCOPE int	TclEvalEx(Tcl_Interp *interp, const char *script,
 			    Tcl_Size numBytes, int flags, Tcl_Size line,
diff --git a/generic/tclStrIdxTree.c b/generic/tclStrIdxTree.c
new file mode 100644
index 0000000..bdb16f2
--- /dev/null
+++ b/generic/tclStrIdxTree.c
@@ -0,0 +1,530 @@
+/*
+ * tclStrIdxTree.c --
+ *
+ *	Contains the routines for managing string index tries in Tcl.
+ *
+ *	This code is back-ported from the tclSE engine, by Serg G. Brester.
+ *
+ * Copyright (c) 2016 by Sergey G. Brester aka sebres. All rights reserved.
+ *
+ * See the file "license.terms" for information on usage and redistribution of
+ * this file, and for a DISCLAIMER OF ALL WARRANTIES.
+ *
+ * -----------------------------------------------------------------------
+ *
+ * String index tries are prepaired structures used for fast greedy search of the string
+ * (index) by unique string prefix as key.
+ *
+ * Index tree build for two lists together can be explained in the following datagram
+ *
+ * Lists:
+ *
+ *	{Januar Februar Maerz April Mai Juni Juli August September Oktober November Dezember}
+ *	{Jnr Fbr Mrz Apr Mai Jni Jli Agt Spt Okt Nvb Dzb}
+ *
+ * Index-Tree:
+ *
+ *	j		 0	 *	...
+ *	 anuar		 1	 *
+ *	 u		 0	 *	a		 0
+ *	  ni		 6	 *	 pril		 4
+ *	  li		 7	 *	 ugust		 8
+ *	 n		 0	 *	 gt		 8
+ *	  r		 1	 *	s		 9
+ *	  i		 6	 *	 eptember	 9
+ *	 li		 7	 *	 pt		 9
+ *	f		 2	 *	oktober		10
+ *	 ebruar		 2	 *	n		11
+ *	 br		 2	 *	 ovember	11
+ *	m		 0	 *	 vb		11
+ *	 a		 0	 *	d		12
+ *	  erz		 3	 *	 ezember	12
+ *	  i		 5	 *	 zb		12
+ *	 rz		 3	 *
+ *	...
+ *
+ * Thereby value 0 shows pure group items (corresponding ambigous matches).
+ * But the group may have a value if it contains only same values
+ * (see for example group "f" above).
+ *
+ * StrIdxTree's are very fast, so:
+ *    build of above-mentioned tree takes about 10 microseconds.
+ *    search of string index in this tree takes fewer as 0.1 microseconds.
+ *
+ */
+
+#include "tclInt.h"
+#include "tclStrIdxTree.h"
+
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * TclStrIdxTreeSearch --
+ *
+ *  Find largest part of string "start" in indexed tree (case sensitive).
+ *
+ *  Also used for building of string index tree.
+ *
+ * Results:
+ *  Return position of UTF character in start after last equal character
+ *  and found item (with parent).
+ *
+ * Side effects:
+ *  None.
+ *
+ *----------------------------------------------------------------------
+ */
+
+const char*
+TclStrIdxTreeSearch(
+    TclStrIdxTree **foundParent, /* Return value of found sub tree (used for tree build) */
+    TclStrIdx	  **foundItem,	 /* Return value of found item */
+    TclStrIdxTree  *tree,	 /* Index tree will be browsed */
+    const char	*start,		 /* UTF string to find in tree */
+    const char	*end)		 /* End of string */
+{
+    TclStrIdxTree *parent = tree, *prevParent = tree;
+    TclStrIdx  *item = tree->firstPtr, *prevItem = NULL;
+    const char *s = start, *f, *cin, *cinf, *prevf = NULL;
+    int offs = 0;
+
+    if (item == NULL) {
+	goto done;
+    }
+
+    /* search in tree */
+    do {
+	cinf = cin = TclGetString(item->key) + offs;
+	f = TclUtfFindEqualNCInLwr(s, end, cin, cin + item->length - offs, &cinf);
+	/* if something was found */
+	if (f > s) {
+	    /* if whole string was found */
+	    if (f >= end) {
+		start = f;
+		goto done;
+	    };
+	    /* set new offset and shift start string */
+	    offs += cinf - cin;
+	    s = f;
+	    /* if match item, go deeper as long as possible */
+	    if (offs >= item->length && item->childTree.firstPtr) {
+		/* save previuosly found item (if not ambigous) for
+		 * possible fallback (few greedy match) */
+		if (item->value != NULL) {
+		    prevf = f;
+		    prevItem = item;
+		    prevParent = parent;
+		}
+		parent = &item->childTree;
+		item = item->childTree.firstPtr;
+		continue;
+	    }
+	    /* no children - return this item and current chars found */
+	    start = f;
+	    goto done;
+	}
+
+	item = item->nextPtr;
+
+    } while (item != NULL);
+
+    /* fallback (few greedy match) not ambigous (has a value) */
+    if (prevItem != NULL) {
+	item = prevItem;
+	parent = prevParent;
+	start = prevf;
+    }
+
+done:
+
+    if (foundParent)
+	*foundParent = parent;
+    if (foundItem)
+	*foundItem = item;
+    return start;
+}
+
+void
+TclStrIdxTreeFree(
+    TclStrIdx *tree)
+{
+    while (tree != NULL) {
+	TclStrIdx *t;
+	Tcl_DecrRefCount(tree->key);
+	if (tree->childTree.firstPtr != NULL) {
+	    TclStrIdxTreeFree(tree->childTree.firstPtr);
+	}
+	t = tree, tree = tree->nextPtr;
+	Tcl_Free(t);
+    }
+}
+
+/*
+ * Several bidirectional list primitives
+ */
+static inline void
+TclStrIdxTreeInsertBranch(
+    TclStrIdxTree *parent,
+    TclStrIdx *item,
+    TclStrIdx *child)
+{
+    if (parent->firstPtr == child)
+	parent->firstPtr = item;
+    if (parent->lastPtr == child)
+	parent->lastPtr = item;
+    if ( (item->nextPtr = child->nextPtr) ) {
+	item->nextPtr->prevPtr = item;
+	child->nextPtr = NULL;
+    }
+    if ( (item->prevPtr = child->prevPtr) ) {
+	item->prevPtr->nextPtr = item;
+	child->prevPtr = NULL;
+    }
+    item->childTree.firstPtr = child;
+    item->childTree.lastPtr = child;
+}
+
+static inline void
+TclStrIdxTreeAppend(
+    TclStrIdxTree *parent,
+    TclStrIdx	   *item)
+{
+    if (parent->lastPtr != NULL) {
+	parent->lastPtr->nextPtr = item;
+    }
+    item->prevPtr = parent->lastPtr;
+    item->nextPtr = NULL;
+    parent->lastPtr = item;
+    if (parent->firstPtr == NULL) {
+	parent->firstPtr = item;
+    }
+}
+
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * TclStrIdxTreeBuildFromList --
+ *
+ * Build or extend string indexed tree from tcl list.
+ * If the values not given the values of built list are indices starts with 1.
+ * Value of 0 is thereby reserved to the ambigous values.
+ *
+ * Important: by multiple lists, optimal tree can be created only if list with
+ * larger strings used firstly.
+ *
+ * Results:
+ *  Returns a standard Tcl result.
+ *
+ * Side effects:
+ *  None.
+ *
+ *----------------------------------------------------------------------
+ */
+
+int
+TclStrIdxTreeBuildFromList(
+    TclStrIdxTree *idxTree,
+    Tcl_Size lstc,
+    Tcl_Obj  **lstv,
+    void **values)
+{
+    Tcl_Obj  **lwrv;
+    Tcl_Size i;
+    int ret = TCL_ERROR;
+    void *val;
+    const char *s, *e, *f;
+    TclStrIdx	*item;
+
+    /* create lowercase reflection of the list keys */
+
+    lwrv = (Tcl_Obj **)Tcl_Alloc(sizeof(Tcl_Obj*) * lstc);
+    if (lwrv == NULL) {
+	return TCL_ERROR;
+    }
+    for (i = 0; i < lstc; i++) {
+	lwrv[i] = Tcl_DuplicateObj(lstv[i]);
+	if (lwrv[i] == NULL) {
+	    return TCL_ERROR;
+	}
+	Tcl_IncrRefCount(lwrv[i]);
+	lwrv[i]->length = Tcl_UtfToLower(TclGetString(lwrv[i]));
+    }
+
+    /* build index tree of the list keys */
+    for (i = 0; i < lstc; i++) {
+	TclStrIdxTree *foundParent = idxTree;
+	e = s = TclGetString(lwrv[i]);
+	e += lwrv[i]->length;
+	val = values ? values[i] : INT2PTR(i+1);
+
+	/* ignore empty keys (impossible to index it) */
+	if (lwrv[i]->length == 0) continue;
+
+	item = NULL;
+	if (idxTree->firstPtr != NULL) {
+	    TclStrIdx  *foundItem;
+	    f = TclStrIdxTreeSearch(&foundParent, &foundItem,
+		idxTree, s, e);
+	    /* if common prefix was found */
+	    if (f > s) {
+		/* ignore element if fulfilled or ambigous */
+		if (f == e) {
+		    continue;
+		}
+		/* if shortest key was found with the same value,
+		 * just replace its current key with longest key */
+		if ( foundItem->value == val
+		  && foundItem->length <= lwrv[i]->length
+		  && foundItem->length <= (f - s) /* only if found item is covered in full */
+		  && foundItem->childTree.firstPtr == NULL
+		) {
+		    Tcl_SetObjRef(foundItem->key, lwrv[i]);
+		    foundItem->length = lwrv[i]->length;
+		    continue;
+		}
+		/* split tree (e. g. j->(jan,jun) + jul == j->(jan,ju->(jun,jul)) )
+		 * but don't split by fulfilled child of found item ( ii->iii->iiii ) */
+		if (foundItem->length != (f - s)) {
+		    /* first split found item (insert one between parent and found + new one) */
+		    item = (TclStrIdx *)Tcl_Alloc(sizeof(TclStrIdx));
+		    if (item == NULL) {
+			goto done;
+		    }
+		    Tcl_InitObjRef(item->key, foundItem->key);
+		    item->length = f - s;
+		    /* set value or mark as ambigous if not the same value of both */
+		    item->value = (foundItem->value == val) ? val : NULL;
+		    /* insert group item between foundParent and foundItem */
+		    TclStrIdxTreeInsertBranch(foundParent, item, foundItem);
+		    foundParent = &item->childTree;
+		} else {
+		    /* the new item should be added as child of found item */
+		    foundParent = &foundItem->childTree;
+		}
+	    }
+	}
+	/* append item at end of found parent */
+	item = (TclStrIdx *)Tcl_Alloc(sizeof(TclStrIdx));
+	if (item == NULL) {
+	    goto done;
+	}
+	item->childTree.lastPtr = item->childTree.firstPtr = NULL;
+	Tcl_InitObjRef(item->key, lwrv[i]);
+	item->length = lwrv[i]->length;
+	item->value = val;
+	TclStrIdxTreeAppend(foundParent, item);
+    };
+
+    ret = TCL_OK;
+
+done:
+
+    if (lwrv != NULL) {
+	for (i = 0; i < lstc; i++) {
+	    Tcl_DecrRefCount(lwrv[i]);
+	}
+	Tcl_Free(lwrv);
+    }
+
+    if (ret != TCL_OK) {
+	if (idxTree->firstPtr != NULL) {
+	    TclStrIdxTreeFree(idxTree->firstPtr);
+	}
+    }
+
+    return ret;
+}
+
+
+static void
+StrIdxTreeObj_DupIntRepProc(Tcl_Obj *srcPtr, Tcl_Obj *copyPtr);
+static void
+StrIdxTreeObj_FreeIntRepProc(Tcl_Obj *objPtr);
+static void
+StrIdxTreeObj_UpdateStringProc(Tcl_Obj *objPtr);
+
+Tcl_ObjType StrIdxTreeObjType = {
+    "str-idx-tree",		    /* name */
+    StrIdxTreeObj_FreeIntRepProc,   /* freeIntRepProc */
+    StrIdxTreeObj_DupIntRepProc,    /* dupIntRepProc */
+    StrIdxTreeObj_UpdateStringProc, /* updateStringProc */
+    NULL,			    /* setFromAnyProc */
+    TCL_OBJTYPE_V0
+};
+
+Tcl_Obj*
+TclStrIdxTreeNewObj()
+{
+    Tcl_Obj *objPtr = Tcl_NewObj();
+    objPtr->internalRep.twoPtrValue.ptr1 = NULL;
+    objPtr->internalRep.twoPtrValue.ptr2 = NULL;
+    objPtr->typePtr = &StrIdxTreeObjType;
+    /* return tree root in internal representation */
+    return objPtr;
+}
+
+static void
+StrIdxTreeObj_DupIntRepProc(Tcl_Obj *srcPtr, Tcl_Obj *copyPtr)
+{
+    /* follow links (smart pointers) */
+    if ( srcPtr->internalRep.twoPtrValue.ptr1 != NULL
+      && srcPtr->internalRep.twoPtrValue.ptr2 == NULL
+    ) {
+	srcPtr = (Tcl_Obj*)srcPtr->internalRep.twoPtrValue.ptr1;
+    }
+    /* create smart pointer to it (ptr1 != NULL, ptr2 = NULL) */
+    Tcl_InitObjRef(*((Tcl_Obj **)&copyPtr->internalRep.twoPtrValue.ptr1),
+	srcPtr);
+    copyPtr->internalRep.twoPtrValue.ptr2 = NULL;
+    copyPtr->typePtr = &StrIdxTreeObjType;
+}
+
+static void
+StrIdxTreeObj_FreeIntRepProc(Tcl_Obj *objPtr)
+{
+    /* follow links (smart pointers) */
+    if ( objPtr->internalRep.twoPtrValue.ptr1 != NULL
+      && objPtr->internalRep.twoPtrValue.ptr2 == NULL
+    ) {
+	/* is a link */
+	Tcl_UnsetObjRef(*((Tcl_Obj **)&objPtr->internalRep.twoPtrValue.ptr1));
+    } else {
+	/* is a tree */
+	TclStrIdxTree *tree = (TclStrIdxTree*)&objPtr->internalRep.twoPtrValue.ptr1;
+	if (tree->firstPtr != NULL) {
+	    TclStrIdxTreeFree(tree->firstPtr);
+	}
+	objPtr->internalRep.twoPtrValue.ptr1 = NULL;
+	objPtr->internalRep.twoPtrValue.ptr2 = NULL;
+    }
+    objPtr->typePtr = NULL;
+};
+
+static void
+StrIdxTreeObj_UpdateStringProc(Tcl_Obj *objPtr)
+{
+    /* currently only dummy empty string possible */
+    objPtr->length = 0;
+    objPtr->bytes = &tclEmptyString;
+};
+
+TclStrIdxTree *
+TclStrIdxTreeGetFromObj(Tcl_Obj *objPtr) {
+    /* follow links (smart pointers) */
+    if (objPtr->typePtr != &StrIdxTreeObjType) {
+	return NULL;
+    }
+    if ( objPtr->internalRep.twoPtrValue.ptr1 != NULL
+      && objPtr->internalRep.twoPtrValue.ptr2 == NULL
+    ) {
+	objPtr = (Tcl_Obj*)objPtr->internalRep.twoPtrValue.ptr1;
+    }
+    /* return tree root in internal representation */
+    return (TclStrIdxTree*)&objPtr->internalRep.twoPtrValue.ptr1;
+}
+
+/*
+ * Several debug primitives
+ */
+#if 0
+/* currently unused, debug resp. test purposes only */
+
+void
+TclStrIdxTreePrint(
+    Tcl_Interp *interp,
+    TclStrIdx  *tree,
+    int offs)
+{
+    Tcl_Obj *obj[2];
+    const char *s;
+    Tcl_InitObjRef(obj[0], Tcl_NewStringObj("::puts", -1));
+    while (tree != NULL) {
+	s = TclGetString(tree->key) + offs;
+	Tcl_InitObjRef(obj[1], Tcl_ObjPrintf("%*s%.*s\t:%d",
+		offs, "", tree->length - offs, s, tree->value));
+	Tcl_PutsObjCmd(NULL, interp, 2, obj);
+	Tcl_UnsetObjRef(obj[1]);
+	if (tree->childTree.firstPtr != NULL) {
+	    TclStrIdxTreePrint(interp, tree->childTree.firstPtr, tree->length);
+	}
+	tree = tree->nextPtr;
+    }
+    Tcl_UnsetObjRef(obj[0]);
+}
+
+
+int
+TclStrIdxTreeTestObjCmd(
+    ClientData clientData, Tcl_Interp *interp,
+    int objc, Tcl_Obj *const objv[])
+{
+    const char *cs, *cin, *ret;
+
+    static const char *const options[] = {
+	"index", "puts-index", "findequal",
+	NULL
+    };
+    enum optionInd {
+	O_INDEX,  O_PUTS_INDEX, O_FINDEQUAL
+    };
+    int optionIndex;
+
+    if (objc < 2) {
+	Tcl_WrongNumArgs(interp, 1, objv, "");
+	return TCL_ERROR;
+    }
+    if (Tcl_GetIndexFromObj(interp, objv[1], options,
+	"option", 0, &optionIndex) != TCL_OK) {
+	Tcl_SetErrorCode(interp, "CLOCK", "badOption",
+		Tcl_GetString(objv[1]), (char *)NULL);
+	return TCL_ERROR;
+    }
+    switch (optionIndex) {
+    case O_FINDEQUAL:
+	if (objc < 4) {
+	    Tcl_WrongNumArgs(interp, 1, objv, "");
+	    return TCL_ERROR;
+	}
+	cs = TclGetString(objv[2]);
+	cin = TclGetString(objv[3]);
+	ret = TclUtfFindEqual(
+	    cs, cs + objv[1]->length, cin, cin + objv[2]->length);
+	Tcl_SetObjResult(interp, Tcl_NewIntObj(ret - cs));
+    break;
+    case O_INDEX:
+    case O_PUTS_INDEX:
+
+    if (1) {
+	Tcl_Obj **lstv;
+	int i, lstc;
+	TclStrIdxTree idxTree = {NULL, NULL};
+	i = 1;
+	while (++i < objc) {
+	    if (TclListObjGetElements(interp, objv[i],
+		    &lstc, &lstv) != TCL_OK) {
+		return TCL_ERROR;
+	    };
+	    TclStrIdxTreeBuildFromList(&idxTree, lstc, lstv, NULL);
+	}
+	if (optionIndex == O_PUTS_INDEX) {
+	    TclStrIdxTreePrint(interp, idxTree.firstPtr, 0);
+	}
+	TclStrIdxTreeFree(idxTree.firstPtr);
+    }
+    break;
+    }
+
+    return TCL_OK;
+}
+
+#endif
+
+/*
+ * Local Variables:
+ * mode: c
+ * c-basic-offset: 4
+ * fill-column: 78
+ * End:
+ */
diff --git a/generic/tclStrIdxTree.h b/generic/tclStrIdxTree.h
new file mode 100644
index 0000000..19e7624
--- /dev/null
+++ b/generic/tclStrIdxTree.h
@@ -0,0 +1,155 @@
+/*
+ * tclStrIdxTree.h --
+ *
+ *	Declarations of string index tries and other primitives currently
+ *  back-ported from tclSE.
+ *
+ * Copyright (c) 2016 Serg G. Brester (aka sebres)
+ *
+ * See the file "license.terms" for information on usage and redistribution
+ * of this file, and for a DISCLAIMER OF ALL WARRANTIES.
+ */
+
+#ifndef _TCLSTRIDXTREE_H
+#define _TCLSTRIDXTREE_H
+
+
+/*
+ * Main structures declarations of index tree and entry
+ */
+
+typedef struct TclStrIdxTree {
+    struct TclStrIdx *firstPtr;
+    struct TclStrIdx *lastPtr;
+} TclStrIdxTree;
+
+typedef struct TclStrIdx {
+    struct TclStrIdxTree childTree;
+    struct TclStrIdx *nextPtr;
+    struct TclStrIdx *prevPtr;
+    Tcl_Obj	*key;
+    int		 length;
+    void	*value;
+} TclStrIdx;
+
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * TclUtfFindEqual, TclUtfFindEqualNC --
+ *
+ *  Find largest part of string cs in string cin (case sensitive and not).
+ *
+ * Results:
+ *  Return position of UTF character in cs after last equal character.
+ *
+ * Side effects:
+ *  None.
+ *
+ *----------------------------------------------------------------------
+ */
+
+static inline const char *
+TclUtfFindEqual(
+    const char *cs,	/* UTF string to find in cin. */
+    const char *cse,	/* End of cs */
+    const char *cin,	/* UTF string will be browsed. */
+    const char *cine)	/* End of cin */
+{
+    const char *ret = cs;
+    Tcl_UniChar ch1, ch2;
+    do {
+	cs += TclUtfToUniChar(cs, &ch1);
+	cin += TclUtfToUniChar(cin, &ch2);
+	if (ch1 != ch2) break;
+    } while ((ret = cs) < cse && cin < cine);
+    return ret;
+}
+
+static inline const char *
+TclUtfFindEqualNC(
+    const char *cs,	/* UTF string to find in cin. */
+    const char *cse,	/* End of cs */
+    const char *cin,	/* UTF string will be browsed. */
+    const char *cine,	/* End of cin */
+    const char	     **cinfnd)	/* Return position in cin */
+{
+    const char *ret = cs;
+    Tcl_UniChar ch1, ch2;
+    do {
+	cs += TclUtfToUniChar(cs, &ch1);
+	cin += TclUtfToUniChar(cin, &ch2);
+	if (ch1 != ch2) {
+	    ch1 = Tcl_UniCharToLower(ch1);
+	    ch2 = Tcl_UniCharToLower(ch2);
+	    if (ch1 != ch2) break;
+	}
+	*cinfnd = cin;
+    } while ((ret = cs) < cse && cin < cine);
+    return ret;
+}
+
+static inline const char *
+TclUtfFindEqualNCInLwr(
+    const char *cs,	/* UTF string (in anycase) to find in cin. */
+    const char *cse,	/* End of cs */
+    const char *cin,	/* UTF string (in lowercase) will be browsed. */
+    const char *cine,	/* End of cin */
+    const char	     **cinfnd)	/* Return position in cin */
+{
+    const char *ret = cs;
+    Tcl_UniChar ch1, ch2;
+    do {
+	cs += TclUtfToUniChar(cs, &ch1);
+	cin += TclUtfToUniChar(cin, &ch2);
+	if (ch1 != ch2) {
+	    ch1 = Tcl_UniCharToLower(ch1);
+	    if (ch1 != ch2) break;
+	}
+	*cinfnd = cin;
+    } while ((ret = cs) < cse && cin < cine);
+    return ret;
+}
+
+/*
+ * Primitives to safe set, reset and free references.
+ */
+
+#define Tcl_UnsetObjRef(obj) \
+  if (obj != NULL) { Tcl_DecrRefCount(obj); obj = NULL; }
+#define Tcl_InitObjRef(obj, val) \
+  obj = val; if (obj) { Tcl_IncrRefCount(obj); }
+#define Tcl_SetObjRef(obj, val) \
+if (1) { \
+  Tcl_Obj *nval = val; \
+  if (obj != nval) { \
+    Tcl_Obj *prev = obj; \
+    Tcl_InitObjRef(obj, nval); \
+    if (prev != NULL) { Tcl_DecrRefCount(prev); }; \
+  } \
+}
+
+/*
+ * Prototypes of module functions.
+ */
+
+MODULE_SCOPE const char*
+		    TclStrIdxTreeSearch(TclStrIdxTree **foundParent,
+			TclStrIdx **foundItem, TclStrIdxTree *tree,
+			const char *start, const char *end);
+
+MODULE_SCOPE int    TclStrIdxTreeBuildFromList(TclStrIdxTree *idxTree,
+			Tcl_Size lstc, Tcl_Obj **lstv, void **values);
+
+MODULE_SCOPE Tcl_Obj*
+		    TclStrIdxTreeNewObj();
+
+MODULE_SCOPE TclStrIdxTree*
+		    TclStrIdxTreeGetFromObj(Tcl_Obj *objPtr);
+
+#if 1
+
+MODULE_SCOPE Tcl_ObjCmdProc TclStrIdxTreeTestObjCmd;
+#endif
+
+#endif /* _TCLSTRIDXTREE_H */