Merge commit 'c8bc058c566bbcbcd23e732197d64fecc739008f' as 'tcl8.6'

1 files changed, 6615 insertions, 0 deletions

diff --git a/tcl8.6/generic/tclVar.c b/tcl8.6/generic/tclVar.c
new file mode 100644
index 0000000..3dd6790
--- /dev/null
+++ b/tcl8.6/generic/tclVar.c
@@ -0,0 +1,6615 @@
+/*
+ * tclVar.c --
+ *
+ *	This file contains routines that implement Tcl variables (both scalars
+ *	and arrays).
+ *
+ *	The implementation of arrays is modelled after an initial
+ *	implementation by Mark Diekhans and Karl Lehenbauer.
+ *
+ * Copyright (c) 1987-1994 The Regents of the University of California.
+ * Copyright (c) 1994-1997 Sun Microsystems, Inc.
+ * Copyright (c) 1998-1999 by Scriptics Corporation.
+ * Copyright (c) 2001 by Kevin B. Kenny. All rights reserved.
+ * Copyright (c) 2007 Miguel Sofer
+ *
+ * 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 "tclOOInt.h"
+
+/*
+ * Prototypes for the variable hash key methods.
+ */
+
+static Tcl_HashEntry *	AllocVarEntry(Tcl_HashTable *tablePtr, void *keyPtr);
+static void		FreeVarEntry(Tcl_HashEntry *hPtr);
+static int		CompareVarKeys(void *keyPtr, Tcl_HashEntry *hPtr);
+
+static const Tcl_HashKeyType tclVarHashKeyType = {
+    TCL_HASH_KEY_TYPE_VERSION,	/* version */
+    0,				/* flags */
+    TclHashObjKey,		/* hashKeyProc */
+    CompareVarKeys,		/* compareKeysProc */
+    AllocVarEntry,		/* allocEntryProc */
+    FreeVarEntry		/* freeEntryProc */
+};
+
+static inline Var *	VarHashCreateVar(TclVarHashTable *tablePtr,
+			    Tcl_Obj *key, int *newPtr);
+static inline Var *	VarHashFirstVar(TclVarHashTable *tablePtr,
+			    Tcl_HashSearch *searchPtr);
+static inline Var *	VarHashNextVar(Tcl_HashSearch *searchPtr);
+static inline void	CleanupVar(Var *varPtr, Var *arrayPtr);
+
+#define VarHashGetValue(hPtr) \
+    ((Var *) ((char *)hPtr - TclOffset(VarInHash, entry)))
+
+/*
+ * NOTE: VarHashCreateVar increments the recount of its key argument.
+ * All callers that will call Tcl_DecrRefCount on that argument must
+ * call Tcl_IncrRefCount on it before passing it in.  This requirement
+ * can bubble up to callers of callers .... etc.
+ */
+
+static inline Var *
+VarHashCreateVar(
+    TclVarHashTable *tablePtr,
+    Tcl_Obj *key,
+    int *newPtr)
+{
+    Tcl_HashEntry *hPtr = Tcl_CreateHashEntry(&tablePtr->table,
+	    key, newPtr);
+
+    if (hPtr) {
+	return VarHashGetValue(hPtr);
+    } else {
+	return NULL;
+    }
+}
+
+#define VarHashFindVar(tablePtr, key) \
+    VarHashCreateVar((tablePtr), (key), NULL)
+
+#define VarHashInvalidateEntry(varPtr) \
+    ((varPtr)->flags |= VAR_DEAD_HASH)
+
+#define VarHashDeleteEntry(varPtr) \
+    Tcl_DeleteHashEntry(&(((VarInHash *) varPtr)->entry))
+
+#define VarHashFirstEntry(tablePtr, searchPtr) \
+    Tcl_FirstHashEntry(&(tablePtr)->table, (searchPtr))
+
+#define VarHashNextEntry(searchPtr) \
+    Tcl_NextHashEntry((searchPtr))
+
+static inline Var *
+VarHashFirstVar(
+    TclVarHashTable *tablePtr,
+    Tcl_HashSearch *searchPtr)
+{
+    Tcl_HashEntry *hPtr = VarHashFirstEntry(tablePtr, searchPtr);
+
+    if (hPtr) {
+	return VarHashGetValue(hPtr);
+    } else {
+	return NULL;
+    }
+}
+
+static inline Var *
+VarHashNextVar(
+    Tcl_HashSearch *searchPtr)
+{
+    Tcl_HashEntry *hPtr = VarHashNextEntry(searchPtr);
+
+    if (hPtr) {
+	return VarHashGetValue(hPtr);
+    } else {
+	return NULL;
+    }
+}
+
+#define VarHashGetKey(varPtr) \
+    (((VarInHash *)(varPtr))->entry.key.objPtr)
+
+#define VarHashDeleteTable(tablePtr) \
+    Tcl_DeleteHashTable(&(tablePtr)->table)
+
+/*
+ * The strings below are used to indicate what went wrong when a variable
+ * access is denied.
+ */
+
+static const char *noSuchVar =		"no such variable";
+static const char *isArray =		"variable is array";
+static const char *needArray =		"variable isn't array";
+static const char *noSuchElement =	"no such element in array";
+static const char *danglingElement =
+	"upvar refers to element in deleted array";
+static const char *danglingVar =
+	"upvar refers to variable in deleted namespace";
+static const char *badNamespace =	"parent namespace doesn't exist";
+static const char *missingName =	"missing variable name";
+static const char *isArrayElement =
+	"name refers to an element in an array";
+
+/*
+ * A test to see if we are in a call frame that has local variables. This is
+ * true if we are inside a procedure body.
+ */
+
+#define HasLocalVars(framePtr) ((framePtr)->isProcCallFrame & FRAME_IS_PROC)
+
+/*
+ * The following structure describes an enumerative search in progress on an
+ * array variable; this are invoked with options to the "array" command.
+ */
+
+typedef struct ArraySearch {
+    int id;			/* Integer id used to distinguish among
+				 * multiple concurrent searches for the same
+				 * array. */
+    struct Var *varPtr;		/* Pointer to array variable that's being
+				 * searched. */
+    Tcl_HashSearch search;	/* Info kept by the hash module about progress
+				 * through the array. */
+    Tcl_HashEntry *nextEntry;	/* Non-null means this is the next element to
+				 * be enumerated (it's leftover from the
+				 * Tcl_FirstHashEntry call or from an "array
+				 * anymore" command). NULL means must call
+				 * Tcl_NextHashEntry to get value to
+				 * return. */
+    struct ArraySearch *nextPtr;/* Next in list of all active searches for
+				 * this variable, or NULL if this is the last
+				 * one. */
+} ArraySearch;
+
+/*
+ * Forward references to functions defined later in this file:
+ */
+
+static void		AppendLocals(Tcl_Interp *interp, Tcl_Obj *listPtr,
+			    Tcl_Obj *patternPtr, int includeLinks);
+static void		DeleteSearches(Interp *iPtr, Var *arrayVarPtr);
+static void		DeleteArray(Interp *iPtr, Tcl_Obj *arrayNamePtr,
+			    Var *varPtr, int flags, int index);
+static Tcl_Var		ObjFindNamespaceVar(Tcl_Interp *interp,
+			    Tcl_Obj *namePtr, Tcl_Namespace *contextNsPtr,
+			    int flags);
+static int		ObjMakeUpvar(Tcl_Interp *interp,
+			    CallFrame *framePtr, Tcl_Obj *otherP1Ptr,
+			    const char *otherP2, const int otherFlags,
+			    Tcl_Obj *myNamePtr, int myFlags, int index);
+static ArraySearch *	ParseSearchId(Tcl_Interp *interp, const Var *varPtr,
+			    Tcl_Obj *varNamePtr, Tcl_Obj *handleObj);
+static void		UnsetVarStruct(Var *varPtr, Var *arrayPtr,
+			    Interp *iPtr, Tcl_Obj *part1Ptr,
+			    Tcl_Obj *part2Ptr, int flags, int index);
+static int		SetArraySearchObj(Tcl_Interp *interp,
+			    Tcl_Obj *objPtr);
+
+/*
+ * Functions defined in this file that may be exported in the future for use
+ * by the bytecode compiler and engine or to the public interface.
+ */
+
+MODULE_SCOPE Var *	TclLookupSimpleVar(Tcl_Interp *interp,
+			    Tcl_Obj *varNamePtr, int flags, const int create,
+			    const char **errMsgPtr, int *indexPtr);
+
+static Tcl_DupInternalRepProc	DupLocalVarName;
+static Tcl_FreeInternalRepProc	FreeLocalVarName;
+static Tcl_UpdateStringProc	PanicOnUpdateVarName;
+
+static Tcl_FreeInternalRepProc	FreeParsedVarName;
+static Tcl_DupInternalRepProc	DupParsedVarName;
+static Tcl_UpdateStringProc	UpdateParsedVarName;
+
+static Tcl_UpdateStringProc	PanicOnUpdateVarName;
+static Tcl_SetFromAnyProc	PanicOnSetVarName;
+
+/*
+ * Types of Tcl_Objs used to cache variable lookups.
+ *
+ * localVarName - INTERNALREP DEFINITION:
+ *   twoPtrValue.ptr1:   pointer to name obj in varFramePtr->localCache
+ *			  or NULL if it is this same obj
+ *   twoPtrValue.ptr2: index into locals table
+ *
+ * parsedVarName - INTERNALREP DEFINITION:
+ *   twoPtrValue.ptr1:	pointer to the array name Tcl_Obj, or NULL if it is a
+ *			scalar variable
+ *   twoPtrValue.ptr2:	pointer to the element name string (owned by this
+ *			Tcl_Obj), or NULL if it is a scalar variable
+ */
+
+static const Tcl_ObjType localVarNameType = {
+    "localVarName",
+    FreeLocalVarName, DupLocalVarName, PanicOnUpdateVarName, PanicOnSetVarName
+};
+
+static const Tcl_ObjType tclParsedVarNameType = {
+    "parsedVarName",
+    FreeParsedVarName, DupParsedVarName, UpdateParsedVarName, PanicOnSetVarName
+};
+
+/*
+ * Type of Tcl_Objs used to speed up array searches.
+ *
+ * INTERNALREP DEFINITION:
+ *   twoPtrValue.ptr1:	searchIdNumber (cast to pointer)
+ *   twoPtrValue.ptr2:	variableNameStartInString (cast to pointer)
+ *
+ * Note that the value stored in ptr2 is the offset into the string of the
+ * start of the variable name and not the address of the variable name itself,
+ * as this can be safely copied.
+ */
+
+const Tcl_ObjType tclArraySearchType = {
+    "array search",
+    NULL, NULL, NULL, SetArraySearchObj
+};
+
+Var *
+TclVarHashCreateVar(
+    TclVarHashTable *tablePtr,
+    const char *key,
+    int *newPtr)
+{
+    Tcl_Obj *keyPtr;
+    Var *varPtr;
+
+    keyPtr = Tcl_NewStringObj(key, -1);
+    Tcl_IncrRefCount(keyPtr);
+    varPtr = VarHashCreateVar(tablePtr, keyPtr, newPtr);
+    Tcl_DecrRefCount(keyPtr);
+
+    return varPtr;
+}
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * TclCleanupVar --
+ *
+ *	This function is called when it looks like it may be OK to free up a
+ *	variable's storage. If the variable is in a hashtable, its Var
+ *	structure and hash table entry will be freed along with those of its
+ *	containing array, if any. This function is called, for example, when
+ *	a trace on a variable deletes a variable.
+ *
+ * Results:
+ *	None.
+ *
+ * Side effects:
+ *	If the variable (or its containing array) really is dead and in a
+ *	hashtable, then its Var structure, and possibly its hash table entry,
+ *	is freed up.
+ *
+ *----------------------------------------------------------------------
+ */
+
+static inline void
+CleanupVar(
+    Var *varPtr,		/* Pointer to variable that may be a candidate
+				 * for being expunged. */
+    Var *arrayPtr)		/* Array that contains the variable, or NULL
+				 * if this variable isn't an array element. */
+{
+    if (TclIsVarUndefined(varPtr) && TclIsVarInHash(varPtr)
+	    && !TclIsVarTraced(varPtr)
+	    && (VarHashRefCount(varPtr) == !TclIsVarDeadHash(varPtr))) {
+	if (VarHashRefCount(varPtr) == 0) {
+	    ckfree(varPtr);
+	} else {
+	    VarHashDeleteEntry(varPtr);
+	}
+    }
+    if (arrayPtr != NULL && TclIsVarUndefined(arrayPtr) &&
+	    TclIsVarInHash(arrayPtr) && !TclIsVarTraced(arrayPtr) &&
+	    (VarHashRefCount(arrayPtr) == !TclIsVarDeadHash(arrayPtr))) {
+	if (VarHashRefCount(arrayPtr) == 0) {
+	    ckfree(arrayPtr);
+	} else {
+	    VarHashDeleteEntry(arrayPtr);
+	}
+    }
+}
+
+void
+TclCleanupVar(
+    Var *varPtr,		/* Pointer to variable that may be a candidate
+				 * for being expunged. */
+    Var *arrayPtr)		/* Array that contains the variable, or NULL
+				 * if this variable isn't an array element. */
+{
+    CleanupVar(varPtr, arrayPtr);
+}
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * TclLookupVar --
+ *
+ *	This function is used to locate a variable given its name(s). It has
+ *	been mostly superseded by TclObjLookupVar, it is now only used by the
+ *	trace code. It is kept in tcl8.5 mainly because it is in the internal
+ *	stubs table, so that some extension may be calling it.
+ *
+ * Results:
+ *	The return value is a pointer to the variable structure indicated by
+ *	part1 and part2, or NULL if the variable couldn't be found. If the
+ *	variable is found, *arrayPtrPtr is filled in with the address of the
+ *	variable structure for the array that contains the variable (or NULL
+ *	if the variable is a scalar). If the variable can't be found and
+ *	either createPart1 or createPart2 are 1, a new as-yet-undefined
+ *	(VAR_UNDEFINED) variable structure is created, entered into a hash
+ *	table, and returned.
+ *
+ *	If the variable isn't found and creation wasn't specified, or some
+ *	other error occurs, NULL is returned and an error message is left in
+ *	the interp's result if TCL_LEAVE_ERR_MSG is set in flags.
+ *
+ *	Note: it's possible for the variable returned to be VAR_UNDEFINED even
+ *	if createPart1 or createPart2 are 1 (these only cause the hash table
+ *	entry or array to be created). For example, the variable might be a
+ *	global that has been unset but is still referenced by a procedure, or
+ *	a variable that has been unset but it only being kept in existence (if
+ *	VAR_UNDEFINED) by a trace.
+ *
+ * Side effects:
+ *	New hashtable entries may be created if createPart1 or createPart2
+ *	are 1.
+ *
+ *----------------------------------------------------------------------
+ */
+
+Var *
+TclLookupVar(
+    Tcl_Interp *interp,		/* Interpreter to use for lookup. */
+    const char *part1,		/* If part2 isn't NULL, this is the name of an
+				 * array. Otherwise, this is a full variable
+				 * name that could include a parenthesized
+				 * array element. */
+    const char *part2,		/* Name of element within array, or NULL. */
+    int flags,			/* Only TCL_GLOBAL_ONLY, TCL_NAMESPACE_ONLY,
+				 * and TCL_LEAVE_ERR_MSG bits matter. */
+    const char *msg,		/* Verb to use in error messages, e.g. "read"
+				 * or "set". Only needed if TCL_LEAVE_ERR_MSG
+				 * is set in flags. */
+    int createPart1,		/* If 1, create hash table entry for part 1 of
+				 * name, if it doesn't already exist. If 0,
+				 * return error if it doesn't exist. */
+    int createPart2,		/* If 1, create hash table entry for part 2 of
+				 * name, if it doesn't already exist. If 0,
+				 * return error if it doesn't exist. */
+    Var **arrayPtrPtr)		/* If the name refers to an element of an
+				 * array, *arrayPtrPtr gets filled in with
+				 * address of array variable. Otherwise this
+				 * is set to NULL. */
+{
+    Var *varPtr;
+    Tcl_Obj *part1Ptr = Tcl_NewStringObj(part1, -1);
+
+    if (createPart1) {
+	Tcl_IncrRefCount(part1Ptr);
+    }
+
+    varPtr = TclObjLookupVar(interp, part1Ptr, part2, flags, msg,
+	    createPart1, createPart2, arrayPtrPtr);
+
+    TclDecrRefCount(part1Ptr);
+    return varPtr;
+}
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * TclObjLookupVar, TclObjLookupVarEx --
+ *
+ *	This function is used by virtually all of the variable code to locate
+ *	a variable given its name(s). The parsing into array/element
+ *	components and (if possible) the lookup results are cached in
+ *	part1Ptr, which is converted to one of the varNameTypes.
+ *
+ * Results:
+ *	The return value is a pointer to the variable structure indicated by
+ *	part1Ptr and part2, or NULL if the variable couldn't be found. If *
+ *	the variable is found, *arrayPtrPtr is filled with the address of the
+ *	variable structure for the array that contains the variable (or NULL
+ *	if the variable is a scalar). If the variable can't be found and
+ *	either createPart1 or createPart2 are 1, a new as-yet-undefined
+ *	(VAR_UNDEFINED) variable structure is created, entered into a hash
+ *	table, and returned.
+ *
+ *	If the variable isn't found and creation wasn't specified, or some
+ *	other error occurs, NULL is returned and an error message is left in
+ *	the interp's result if TCL_LEAVE_ERR_MSG is set in flags.
+ *
+ *	Note: it's possible for the variable returned to be VAR_UNDEFINED even
+ *	if createPart1 or createPart2 are 1 (these only cause the hash table
+ *	entry or array to be created). For example, the variable might be a
+ *	global that has been unset but is still referenced by a procedure, or
+ *	a variable that has been unset but it only being kept in existence (if
+ *	VAR_UNDEFINED) by a trace.
+ *
+ * Side effects:
+ *	New hashtable entries may be created if createPart1 or createPart2
+ *	are 1. The object part1Ptr is converted to one of localVarNameType,
+ *	tclNsVarNameType or tclParsedVarNameType and caches as much of the
+ *	lookup as it can.
+ *	When createPart1 is 1, callers must IncrRefCount part1Ptr if they
+ *	plan to DecrRefCount it.
+ *
+ *----------------------------------------------------------------------
+ */
+
+Var *
+TclObjLookupVar(
+    Tcl_Interp *interp,		/* Interpreter to use for lookup. */
+    register Tcl_Obj *part1Ptr,	/* If part2 isn't NULL, this is the name of an
+				 * array. Otherwise, this is a full variable
+				 * name that could include a parenthesized
+				 * array element. */
+    const char *part2,		/* Name of element within array, or NULL. */
+    int flags,			/* Only TCL_GLOBAL_ONLY, TCL_NAMESPACE_ONLY,
+				 * and TCL_LEAVE_ERR_MSG bits matter. */
+    const char *msg,		/* Verb to use in error messages, e.g. "read"
+				 * or "set". Only needed if TCL_LEAVE_ERR_MSG
+				 * is set in flags. */
+    const int createPart1,	/* If 1, create hash table entry for part 1 of
+				 * name, if it doesn't already exist. If 0,
+				 * return error if it doesn't exist. */
+    const int createPart2,	/* If 1, create hash table entry for part 2 of
+				 * name, if it doesn't already exist. If 0,
+				 * return error if it doesn't exist. */
+    Var **arrayPtrPtr)		/* If the name refers to an element of an
+				 * array, *arrayPtrPtr gets filled in with
+				 * address of array variable. Otherwise this
+				 * is set to NULL. */
+{
+    Tcl_Obj *part2Ptr = NULL;
+    Var *resPtr;
+
+    if (part2) {
+	part2Ptr = Tcl_NewStringObj(part2, -1);
+	if (createPart2) {
+	    Tcl_IncrRefCount(part2Ptr);
+	}
+    }
+
+    resPtr = TclObjLookupVarEx(interp, part1Ptr, part2Ptr,
+	    flags, msg, createPart1, createPart2, arrayPtrPtr);
+
+    if (part2Ptr) {
+	Tcl_DecrRefCount(part2Ptr);
+    }
+
+    return resPtr;
+}
+
+/*
+ *	When createPart1 is 1, callers must IncrRefCount part1Ptr if they
+ *	plan to DecrRefCount it.
+ *	When createPart2 is 1, callers must IncrRefCount part2Ptr if they
+ *	plan to DecrRefCount it.
+ */
+Var *
+TclObjLookupVarEx(
+    Tcl_Interp *interp,		/* Interpreter to use for lookup. */
+    Tcl_Obj *part1Ptr,		/* If part2Ptr isn't NULL, this is the name of
+				 * an array. Otherwise, this is a full
+				 * variable name that could include a
+				 * parenthesized array element. */
+    Tcl_Obj *part2Ptr,		/* Name of element within array, or NULL. */
+    int flags,			/* Only TCL_GLOBAL_ONLY, TCL_NAMESPACE_ONLY,
+				 * and TCL_LEAVE_ERR_MSG bits matter. */
+    const char *msg,		/* Verb to use in error messages, e.g. "read"
+				 * or "set". Only needed if TCL_LEAVE_ERR_MSG
+				 * is set in flags. */
+    const int createPart1,	/* If 1, create hash table entry for part 1 of
+				 * name, if it doesn't already exist. If 0,
+				 * return error if it doesn't exist. */
+    const int createPart2,	/* If 1, create hash table entry for part 2 of
+				 * name, if it doesn't already exist. If 0,
+				 * return error if it doesn't exist. */
+    Var **arrayPtrPtr)		/* If the name refers to an element of an
+				 * array, *arrayPtrPtr gets filled in with
+				 * address of array variable. Otherwise this
+				 * is set to NULL. */
+{
+    Interp *iPtr = (Interp *) interp;
+    register Var *varPtr;	/* Points to the variable's in-frame Var
+				 * structure. */
+    const char *part1;
+    int index, len1, len2;
+    int parsed = 0;
+    Tcl_Obj *objPtr;
+    const Tcl_ObjType *typePtr = part1Ptr->typePtr;
+    const char *errMsg = NULL;
+    CallFrame *varFramePtr = iPtr->varFramePtr;
+    const char *part2 = part2Ptr? TclGetString(part2Ptr):NULL;
+    char *newPart2 = NULL;
+    *arrayPtrPtr = NULL;
+
+    if (typePtr == &localVarNameType) {
+	int localIndex;
+
+    localVarNameTypeHandling:
+	localIndex = PTR2INT(part1Ptr->internalRep.twoPtrValue.ptr2);
+	if (HasLocalVars(varFramePtr)
+		&& !(flags & (TCL_GLOBAL_ONLY | TCL_NAMESPACE_ONLY))
+		&& (localIndex < varFramePtr->numCompiledLocals)) {
+	    /*
+	     * Use the cached index if the names coincide.
+	     */
+
+	    Tcl_Obj *namePtr = part1Ptr->internalRep.twoPtrValue.ptr1;
+	    Tcl_Obj *checkNamePtr = localName(iPtr->varFramePtr, localIndex);
+
+	    if ((!namePtr && (checkNamePtr == part1Ptr)) ||
+		    (namePtr && (checkNamePtr == namePtr))) {
+		varPtr = (Var *) &(varFramePtr->compiledLocals[localIndex]);
+		goto donePart1;
+	    }
+	}
+	goto doneParsing;
+    }
+
+    /*
+     * If part1Ptr is a tclParsedVarNameType, separate it into the pre-parsed
+     * parts.
+     */
+
+    if (typePtr == &tclParsedVarNameType) {
+	if (part1Ptr->internalRep.twoPtrValue.ptr1 != NULL) {
+	    if (part2Ptr != NULL) {
+		/*
+		 * ERROR: part1Ptr is already an array element, cannot specify
+		 * a part2.
+		 */
+
+		if (flags & TCL_LEAVE_ERR_MSG) {
+		    TclObjVarErrMsg(interp, part1Ptr, part2Ptr, msg,
+			    noSuchVar, -1);
+		    Tcl_SetErrorCode(interp, "TCL", "VALUE", "VARNAME", NULL);
+		}
+		return NULL;
+	    }
+	    part2 = newPart2 = part1Ptr->internalRep.twoPtrValue.ptr2;
+	    if (newPart2) {
+		part2Ptr = Tcl_NewStringObj(newPart2, -1);
+		if (createPart2) {
+		    Tcl_IncrRefCount(part2Ptr);
+		}
+	    }
+	    part1Ptr = part1Ptr->internalRep.twoPtrValue.ptr1;
+	    typePtr = part1Ptr->typePtr;
+	    if (typePtr == &localVarNameType) {
+		goto localVarNameTypeHandling;
+	    }
+	}
+	parsed = 1;
+    }
+    part1 = TclGetStringFromObj(part1Ptr, &len1);
+
+    if (!parsed && len1 && (*(part1 + len1 - 1) == ')')) {
+	/*
+	 * part1Ptr is possibly an unparsed array element.
+	 */
+
+	register int i;
+
+	len2 = -1;
+	for (i = 0; i < len1; i++) {
+	    if (*(part1 + i) == '(') {
+		if (part2Ptr != NULL) {
+		    if (flags & TCL_LEAVE_ERR_MSG) {
+			TclObjVarErrMsg(interp, part1Ptr, part2Ptr, msg,
+				needArray, -1);
+			Tcl_SetErrorCode(interp, "TCL", "VALUE", "VARNAME",
+				NULL);
+		    }
+		    return NULL;
+		}
+
+		/*
+		 * part1Ptr points to an array element; first copy the element
+		 * name to a new string part2.
+		 */
+
+		part2 = part1 + i + 1;
+		len2 = len1 - i - 2;
+		len1 = i;
+
+		newPart2 = ckalloc(len2 + 1);
+		memcpy(newPart2, part2, (unsigned) len2);
+		*(newPart2+len2) = '\0';
+		part2 = newPart2;
+		part2Ptr = Tcl_NewStringObj(newPart2, -1);
+		if (createPart2) {
+		    Tcl_IncrRefCount(part2Ptr);
+		}
+
+		/*
+		 * Free the internal rep of the original part1Ptr, now renamed
+		 * objPtr, and set it to tclParsedVarNameType.
+		 */
+
+		objPtr = part1Ptr;
+		TclFreeIntRep(objPtr);
+		objPtr->typePtr = &tclParsedVarNameType;
+
+		/*
+		 * Define a new string object to hold the new part1Ptr, i.e.,
+		 * the array name. Set the internal rep of objPtr, reset
+		 * typePtr and part1 to contain the references to the array
+		 * name.
+		 */
+
+		TclNewStringObj(part1Ptr, part1, len1);
+		Tcl_IncrRefCount(part1Ptr);
+
+		objPtr->internalRep.twoPtrValue.ptr1 = part1Ptr;
+		objPtr->internalRep.twoPtrValue.ptr2 = (void *) part2;
+
+		typePtr = part1Ptr->typePtr;
+		part1 = TclGetString(part1Ptr);
+		break;
+	    }
+	}
+    }
+
+  doneParsing:
+    /*
+     * part1Ptr is not an array element; look it up, and convert it to one of
+     * the cached types if possible.
+     */
+
+    TclFreeIntRep(part1Ptr);
+
+    varPtr = TclLookupSimpleVar(interp, part1Ptr, flags, createPart1,
+	    &errMsg, &index);
+    if (varPtr == NULL) {
+	if ((errMsg != NULL) && (flags & TCL_LEAVE_ERR_MSG)) {
+	    TclObjVarErrMsg(interp, part1Ptr, part2Ptr, msg, errMsg, -1);
+	    Tcl_SetErrorCode(interp, "TCL", "LOOKUP", "VARNAME",
+		    TclGetString(part1Ptr), NULL);
+	}
+	if (newPart2) {
+	    Tcl_DecrRefCount(part2Ptr);
+	}
+	return NULL;
+    }
+
+    /*
+     * Cache the newly found variable if possible.
+     */
+
+    if (index >= 0) {
+	/*
+	 * An indexed local variable.
+	 */
+	Tcl_Obj *cachedNamePtr = localName(iPtr->varFramePtr, index);
+
+	part1Ptr->typePtr = &localVarNameType;
+	if (part1Ptr != cachedNamePtr) {
+	    part1Ptr->internalRep.twoPtrValue.ptr1 = cachedNamePtr;
+	    Tcl_IncrRefCount(cachedNamePtr);
+	    if (cachedNamePtr->typePtr != &localVarNameType
+		    || cachedNamePtr->internalRep.twoPtrValue.ptr1 != NULL) {
+	        TclFreeIntRep(cachedNamePtr);
+	    }
+	} else {
+	    part1Ptr->internalRep.twoPtrValue.ptr1 = NULL;
+	}
+	part1Ptr->internalRep.twoPtrValue.ptr2 = INT2PTR(index);
+    } else {
+	/*
+	 * At least mark part1Ptr as already parsed.
+	 */
+
+	part1Ptr->typePtr = &tclParsedVarNameType;
+	part1Ptr->internalRep.twoPtrValue.ptr1 = NULL;
+	part1Ptr->internalRep.twoPtrValue.ptr2 = NULL;
+    }
+
+  donePart1:
+    while (TclIsVarLink(varPtr)) {
+	varPtr = varPtr->value.linkPtr;
+    }
+
+    if (part2Ptr != NULL) {
+	/*
+	 * Array element sought: look it up.
+	 */
+
+	*arrayPtrPtr = varPtr;
+	varPtr = TclLookupArrayElement(interp, part1Ptr, part2Ptr, flags, msg,
+		createPart1, createPart2, varPtr, -1);
+	if (newPart2) {
+	    Tcl_DecrRefCount(part2Ptr);
+	}
+    }
+    return varPtr;
+}
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * TclLookupSimpleVar --
+ *
+ *	This function is used by to locate a simple variable (i.e., not an
+ *	array element) given its name.
+ *
+ * Results:
+ *	The return value is a pointer to the variable structure indicated by
+ *	varName, or NULL if the variable couldn't be found. If the variable
+ *	can't be found and create is 1, a new as-yet-undefined (VAR_UNDEFINED)
+ *	variable structure is created, entered into a hash table, and
+ *	returned.
+ *
+ *	If the current CallFrame corresponds to a proc and the variable found
+ *	is one of the compiledLocals, its index is placed in *indexPtr.
+ *	Otherwise, *indexPtr will be set to (according to the needs of
+ *	TclObjLookupVar):
+ *	    -1 a global reference
+ *	    -2 a reference to a namespace variable
+ *	    -3 a non-cachable reference, i.e., one of:
+ *		. non-indexed local var
+ *		. a reference of unknown origin;
+ *		. resolution by a namespace or interp resolver
+ *
+ *	If the variable isn't found and creation wasn't specified, or some
+ *	other error occurs, NULL is returned and the corresponding error
+ *	message is left in *errMsgPtr.
+ *
+ *	Note: it's possible for the variable returned to be VAR_UNDEFINED even
+ *	if create is 1 (this only causes the hash table entry to be created).
+ *	For example, the variable might be a global that has been unset but is
+ *	still referenced by a procedure, or a variable that has been unset but
+ *	it only being kept in existence (if VAR_UNDEFINED) by a trace.
+ *
+ * Side effects:
+ *	A new hashtable entry may be created if create is 1.
+ *	Callers must Incr varNamePtr if they plan to Decr it if create is 1.
+ *
+ *----------------------------------------------------------------------
+ */
+
+Var *
+TclLookupSimpleVar(
+    Tcl_Interp *interp,		/* Interpreter to use for lookup. */
+    Tcl_Obj *varNamePtr,	/* This is a simple variable name that could
+				 * represent a scalar or an array. */
+    int flags,			/* Only TCL_GLOBAL_ONLY, TCL_NAMESPACE_ONLY,
+				 * TCL_AVOID_RESOLVERS and TCL_LEAVE_ERR_MSG
+				 * bits matter. */
+    const int create,		/* If 1, create hash table entry for varname,
+				 * if it doesn't already exist. If 0, return
+				 * error if it doesn't exist. */
+    const char **errMsgPtr,
+    int *indexPtr)
+{
+    Interp *iPtr = (Interp *) interp;
+    CallFrame *varFramePtr = iPtr->varFramePtr;
+				/* Points to the procedure call frame whose
+				 * variables are currently in use. Same as the
+				 * current procedure's frame, if any, unless
+				 * an "uplevel" is executing. */
+    TclVarHashTable *tablePtr;	/* Points to the hashtable, if any, in which
+				 * to look up the variable. */
+    Tcl_Var var;		/* Used to search for global names. */
+    Var *varPtr;		/* Points to the Var structure returned for
+				 * the variable. */
+    Namespace *varNsPtr, *cxtNsPtr, *dummy1Ptr, *dummy2Ptr;
+    ResolverScheme *resPtr;
+    int isNew, i, result, varLen;
+    const char *varName = TclGetStringFromObj(varNamePtr, &varLen);
+
+    varPtr = NULL;
+    varNsPtr = NULL;		/* Set non-NULL if a nonlocal variable. */
+    *indexPtr = -3;
+
+    if (flags & TCL_GLOBAL_ONLY) {
+	cxtNsPtr = iPtr->globalNsPtr;
+    } else {
+	cxtNsPtr = iPtr->varFramePtr->nsPtr;
+    }
+
+    /*
+     * If this namespace has a variable resolver, then give it first crack at
+     * the variable resolution. It may return a Tcl_Var value, it may signal
+     * to continue onward, or it may signal an error.
+     */
+
+    if ((cxtNsPtr->varResProc != NULL || iPtr->resolverPtr != NULL)
+	    && !(flags & TCL_AVOID_RESOLVERS)) {
+	resPtr = iPtr->resolverPtr;
+	if (cxtNsPtr->varResProc) {
+	    result = cxtNsPtr->varResProc(interp, varName,
+		    (Tcl_Namespace *) cxtNsPtr, flags, &var);
+	} else {
+	    result = TCL_CONTINUE;
+	}
+
+	while (result == TCL_CONTINUE && resPtr) {
+	    if (resPtr->varResProc) {
+		result = resPtr->varResProc(interp, varName,
+			(Tcl_Namespace *) cxtNsPtr, flags, &var);
+	    }
+	    resPtr = resPtr->nextPtr;
+	}
+
+	if (result == TCL_OK) {
+	    return (Var *) var;
+	} else if (result != TCL_CONTINUE) {
+	    return NULL;
+	}
+    }
+
+    /*
+     * Look up varName. Look it up as either a namespace variable or as a
+     * local variable in a procedure call frame (varFramePtr). Interpret
+     * varName as a namespace variable if:
+     *    1) so requested by a TCL_GLOBAL_ONLY or TCL_NAMESPACE_ONLY flag,
+     *    2) there is no active frame (we're at the global :: scope),
+     *    3) the active frame was pushed to define the namespace context for a
+     *	     "namespace eval" or "namespace inscope" command,
+     *    4) the name has namespace qualifiers ("::"s).
+     * Otherwise, if varName is a local variable, search first in the frame's
+     * array of compiler-allocated local variables, then in its hashtable for
+     * runtime-created local variables.
+     *
+     * If create and the variable isn't found, create the variable and, if
+     * necessary, create varFramePtr's local var hashtable.
+     */
+
+    if (((flags & (TCL_GLOBAL_ONLY | TCL_NAMESPACE_ONLY)) != 0)
+	    || !HasLocalVars(varFramePtr)
+	    || (strstr(varName, "::") != NULL)) {
+	const char *tail;
+	int lookGlobal = (flags & TCL_GLOBAL_ONLY)
+		|| (cxtNsPtr == iPtr->globalNsPtr)
+		|| ((*varName == ':') && (*(varName+1) == ':'));
+
+	if (lookGlobal) {
+	    *indexPtr = -1;
+	    flags = (flags | TCL_GLOBAL_ONLY) & ~TCL_NAMESPACE_ONLY;
+	} else {
+	    if (flags & TCL_AVOID_RESOLVERS) {
+		flags = (flags | TCL_NAMESPACE_ONLY);
+	    }
+	    if (flags & TCL_NAMESPACE_ONLY) {
+		*indexPtr = -2;
+	    }
+	}
+
+	/*
+	 * Don't pass TCL_LEAVE_ERR_MSG, we may yet create the variable, or
+	 * otherwise generate our own error!
+	 */
+
+	varPtr = (Var *) ObjFindNamespaceVar(interp, varNamePtr,
+		(Tcl_Namespace *) cxtNsPtr,
+		(flags | TCL_AVOID_RESOLVERS) & ~TCL_LEAVE_ERR_MSG);
+	if (varPtr == NULL) {
+	    Tcl_Obj *tailPtr;
+
+	    if (create) {	/* Var wasn't found so create it. */
+		TclGetNamespaceForQualName(interp, varName, cxtNsPtr,
+			flags, &varNsPtr, &dummy1Ptr, &dummy2Ptr, &tail);
+		if (varNsPtr == NULL) {
+		    *errMsgPtr = badNamespace;
+		    return NULL;
+		} else if (tail == NULL) {
+		    *errMsgPtr = missingName;
+		    return NULL;
+		}
+		if (tail != varName) {
+		    tailPtr = Tcl_NewStringObj(tail, -1);
+		} else {
+		    tailPtr = varNamePtr;
+		}
+		varPtr = VarHashCreateVar(&varNsPtr->varTable, tailPtr,
+			&isNew);
+		if (lookGlobal) {
+		    /*
+		     * The variable was created starting from the global
+		     * namespace: a global reference is returned even if it
+		     * wasn't explicitly requested.
+		     */
+
+		    *indexPtr = -1;
+		} else {
+		    *indexPtr = -2;
+		}
+	    } else {		/* Var wasn't found and not to create it. */
+		*errMsgPtr = noSuchVar;
+		return NULL;
+	    }
+	}
+    } else {			/* Local var: look in frame varFramePtr. */
+	int localLen, localCt = varFramePtr->numCompiledLocals;
+	Tcl_Obj **objPtrPtr = &varFramePtr->localCachePtr->varName0;
+	const char *localNameStr;
+
+	for (i=0 ; i<localCt ; i++, objPtrPtr++) {
+	    register Tcl_Obj *objPtr = *objPtrPtr;
+
+	    if (objPtr) {
+		localNameStr = TclGetStringFromObj(objPtr, &localLen);
+
+		if ((varLen == localLen) && (varName[0] == localNameStr[0])
+			&& !memcmp(varName, localNameStr, varLen)) {
+		    *indexPtr = i;
+		    return (Var *) &varFramePtr->compiledLocals[i];
+		}
+	    }
+	}
+	tablePtr = varFramePtr->varTablePtr;
+	if (create) {
+	    if (tablePtr == NULL) {
+		tablePtr = ckalloc(sizeof(TclVarHashTable));
+		TclInitVarHashTable(tablePtr, NULL);
+		varFramePtr->varTablePtr = tablePtr;
+	    }
+	    varPtr = VarHashCreateVar(tablePtr, varNamePtr, &isNew);
+	} else {
+	    varPtr = NULL;
+	    if (tablePtr != NULL) {
+		varPtr = VarHashFindVar(tablePtr, varNamePtr);
+	    }
+	    if (varPtr == NULL) {
+		*errMsgPtr = noSuchVar;
+	    }
+	}
+    }
+    return varPtr;
+}
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * TclLookupArrayElement --
+ *
+ *	This function is used to locate a variable which is in an array's
+ *	hashtable given a pointer to the array's Var structure and the
+ *	element's name.
+ *
+ * Results:
+ *	The return value is a pointer to the variable structure , or NULL if
+ *	the variable couldn't be found.
+ *
+ *	If arrayPtr points to a variable that isn't an array and createPart1
+ *	is 1, the corresponding variable will be converted to an array.
+ *	Otherwise, NULL is returned and an error message is left in the
+ *	interp's result if TCL_LEAVE_ERR_MSG is set in flags.
+ *
+ *	If the variable is not found and createPart2 is 1, the variable is
+ *	created. Otherwise, NULL is returned and an error message is left in
+ *	the interp's result if TCL_LEAVE_ERR_MSG is set in flags.
+ *
+ *	Note: it's possible for the variable returned to be VAR_UNDEFINED even
+ *	if createPart1 or createPart2 are 1 (these only cause the hash table
+ *	entry or array to be created). For example, the variable might be a
+ *	global that has been unset but is still referenced by a procedure, or
+ *	a variable that has been unset but it only being kept in existence (if
+ *	VAR_UNDEFINED) by a trace.
+ *
+ * Side effects:
+ *	The variable at arrayPtr may be converted to be an array if
+ *	createPart1 is 1. A new hashtable entry may be created if createPart2
+ *	is 1.
+ *	When createElem is 1, callers must incr elNamePtr if they plan
+ *	to decr it.
+ *
+ *----------------------------------------------------------------------
+ */
+
+Var *
+TclLookupArrayElement(
+    Tcl_Interp *interp,		/* Interpreter to use for lookup. */
+    Tcl_Obj *arrayNamePtr,	/* This is the name of the array, or NULL if
+				 * index>= 0. */
+    Tcl_Obj *elNamePtr,		/* Name of element within array. */
+    const int flags,		/* Only TCL_LEAVE_ERR_MSG bit matters. */
+    const char *msg,		/* Verb to use in error messages, e.g. "read"
+				 * or "set". Only needed if TCL_LEAVE_ERR_MSG
+				 * is set in flags. */
+    const int createArray,	/* If 1, transform arrayName to be an array if
+				 * it isn't one yet and the transformation is
+				 * possible. If 0, return error if it isn't
+				 * already an array. */
+    const int createElem,	/* If 1, create hash table entry for the
+				 * element, if it doesn't already exist. If 0,
+				 * return error if it doesn't exist. */
+    Var *arrayPtr,		/* Pointer to the array's Var structure. */
+    int index)			/* If >=0, the index of the local array. */
+{
+    int isNew;
+    Var *varPtr;
+    TclVarHashTable *tablePtr;
+    Namespace *nsPtr;
+
+    /*
+     * We're dealing with an array element. Make sure the variable is an array
+     * and look up the element (create the element if desired).
+     */
+
+    if (TclIsVarUndefined(arrayPtr) && !TclIsVarArrayElement(arrayPtr)) {
+	if (!createArray) {
+	    if (flags & TCL_LEAVE_ERR_MSG) {
+		TclObjVarErrMsg(interp, arrayNamePtr, elNamePtr, msg,
+			noSuchVar, index);
+		Tcl_SetErrorCode(interp, "TCL", "LOOKUP", "VARNAME",
+			arrayNamePtr?TclGetString(arrayNamePtr):NULL, NULL);
+	    }
+	    return NULL;
+	}
+
+	/*
+	 * Make sure we are not resurrecting a namespace variable from a
+	 * deleted namespace!
+	 */
+
+	if (TclIsVarDeadHash(arrayPtr)) {
+	    if (flags & TCL_LEAVE_ERR_MSG) {
+		TclObjVarErrMsg(interp, arrayNamePtr, elNamePtr, msg,
+			danglingVar, index);
+		Tcl_SetErrorCode(interp, "TCL", "LOOKUP", "VARNAME",
+			arrayNamePtr?TclGetString(arrayNamePtr):NULL, NULL);
+	    }
+	    return NULL;
+	}
+
+	TclSetVarArray(arrayPtr);
+	tablePtr = ckalloc(sizeof(TclVarHashTable));
+	arrayPtr->value.tablePtr = tablePtr;
+
+	if (TclIsVarInHash(arrayPtr) && TclGetVarNsPtr(arrayPtr)) {
+	    nsPtr = TclGetVarNsPtr(arrayPtr);
+	} else {
+	    nsPtr = NULL;
+	}
+	TclInitVarHashTable(arrayPtr->value.tablePtr, nsPtr);
+    } else if (!TclIsVarArray(arrayPtr)) {
+	if (flags & TCL_LEAVE_ERR_MSG) {
+	    TclObjVarErrMsg(interp, arrayNamePtr, elNamePtr, msg, needArray,
+		    index);
+	    Tcl_SetErrorCode(interp, "TCL", "LOOKUP", "VARNAME",
+		    arrayNamePtr?TclGetString(arrayNamePtr):NULL, NULL);
+	}
+	return NULL;
+    }
+
+    if (createElem) {
+	varPtr = VarHashCreateVar(arrayPtr->value.tablePtr, elNamePtr,
+		&isNew);
+	if (isNew) {
+	    if (arrayPtr->flags & VAR_SEARCH_ACTIVE) {
+		DeleteSearches((Interp *) interp, arrayPtr);
+	    }
+	    TclSetVarArrayElement(varPtr);
+	}
+    } else {
+	varPtr = VarHashFindVar(arrayPtr->value.tablePtr, elNamePtr);
+	if (varPtr == NULL) {
+	    if (flags & TCL_LEAVE_ERR_MSG) {
+		TclObjVarErrMsg(interp, arrayNamePtr, elNamePtr, msg,
+			noSuchElement, index);
+		Tcl_SetErrorCode(interp, "TCL", "LOOKUP", "ELEMENT",
+			TclGetString(elNamePtr), NULL);
+	    }
+	}
+    }
+    return varPtr;
+}
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * Tcl_GetVar --
+ *
+ *	Return the value of a Tcl variable as a string.
+ *
+ * Results:
+ *	The return value points to the current value of varName as a string.
+ *	If the variable is not defined or can't be read because of a clash in
+ *	array usage then a NULL pointer is returned and an error message is
+ *	left in the interp's result if the TCL_LEAVE_ERR_MSG flag is set.
+ *	Note: the return value is only valid up until the next change to the
+ *	variable; if you depend on the value lasting longer than that, then
+ *	make yourself a private copy.
+ *
+ * Side effects:
+ *	None.
+ *
+ *----------------------------------------------------------------------
+ */
+
+#undef Tcl_GetVar
+const char *
+Tcl_GetVar(
+    Tcl_Interp *interp,		/* Command interpreter in which varName is to
+				 * be looked up. */
+    const char *varName,	/* Name of a variable in interp. */
+    int flags)			/* OR-ed combination of TCL_GLOBAL_ONLY,
+				 * TCL_NAMESPACE_ONLY or TCL_LEAVE_ERR_MSG
+				 * bits. */
+{
+    Tcl_Obj *varNamePtr = Tcl_NewStringObj(varName, -1);
+    Tcl_Obj *resultPtr = Tcl_ObjGetVar2(interp, varNamePtr, NULL, flags);
+
+    TclDecrRefCount(varNamePtr);
+
+    if (resultPtr == NULL) {
+	return NULL;
+    }
+    return TclGetString(resultPtr);
+}
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * Tcl_GetVar2 --
+ *
+ *	Return the value of a Tcl variable as a string, given a two-part name
+ *	consisting of array name and element within array.
+ *
+ * Results:
+ *	The return value points to the current value of the variable given by
+ *	part1 and part2 as a string. If the specified variable doesn't exist,
+ *	or if there is a clash in array usage, then NULL is returned and a
+ *	message will be left in the interp's result if the TCL_LEAVE_ERR_MSG
+ *	flag is set. Note: the return value is only valid up until the next
+ *	change to the variable; if you depend on the value lasting longer than
+ *	that, then make yourself a private copy.
+ *
+ * Side effects:
+ *	None.
+ *
+ *----------------------------------------------------------------------
+ */
+
+const char *
+Tcl_GetVar2(
+    Tcl_Interp *interp,		/* Command interpreter in which variable is to
+				 * be looked up. */
+    const char *part1,		/* Name of an array (if part2 is non-NULL) or
+				 * the name of a variable. */
+    const char *part2,		/* If non-NULL, gives the name of an element
+				 * in the array part1. */
+    int flags)			/* OR-ed combination of TCL_GLOBAL_ONLY,
+				 * TCL_NAMESPACE_ONLY and TCL_LEAVE_ERR_MSG *
+				 * bits. */
+{
+    Tcl_Obj *resultPtr;
+    Tcl_Obj *part2Ptr = NULL, *part1Ptr = Tcl_NewStringObj(part1, -1);
+
+    if (part2) {
+	part2Ptr = Tcl_NewStringObj(part2, -1);
+	Tcl_IncrRefCount(part2Ptr);
+    }
+
+    resultPtr = Tcl_ObjGetVar2(interp, part1Ptr, part2Ptr, flags);
+
+    Tcl_DecrRefCount(part1Ptr);
+    if (part2Ptr) {
+	Tcl_DecrRefCount(part2Ptr);
+    }
+    if (resultPtr == NULL) {
+	return NULL;
+    }
+    return TclGetString(resultPtr);
+}
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * Tcl_GetVar2Ex --
+ *
+ *	Return the value of a Tcl variable as a Tcl object, given a two-part
+ *	name consisting of array name and element within array.
+ *
+ * Results:
+ *	The return value points to the current object value of the variable
+ *	given by part1Ptr and part2Ptr. If the specified variable doesn't
+ *	exist, or if there is a clash in array usage, then NULL is returned
+ *	and a message will be left in the interpreter's result if the
+ *	TCL_LEAVE_ERR_MSG flag is set.
+ *
+ * Side effects:
+ *	The ref count for the returned object is _not_ incremented to reflect
+ *	the returned reference; if you want to keep a reference to the object
+ *	you must increment its ref count yourself.
+ *
+ *----------------------------------------------------------------------
+ */
+
+Tcl_Obj *
+Tcl_GetVar2Ex(
+    Tcl_Interp *interp,		/* Command interpreter in which variable is to
+				 * be looked up. */
+    const char *part1,		/* Name of an array (if part2 is non-NULL) or
+				 * the name of a variable. */
+    const char *part2,		/* If non-NULL, gives the name of an element
+				 * in the array part1. */
+    int flags)			/* OR-ed combination of TCL_GLOBAL_ONLY, and
+				 * TCL_LEAVE_ERR_MSG bits. */
+{
+    Tcl_Obj *resPtr, *part2Ptr = NULL, *part1Ptr = Tcl_NewStringObj(part1, -1);
+
+    if (part2) {
+	part2Ptr = Tcl_NewStringObj(part2, -1);
+	Tcl_IncrRefCount(part2Ptr);
+    }
+
+    resPtr = Tcl_ObjGetVar2(interp, part1Ptr, part2Ptr, flags);
+
+    Tcl_DecrRefCount(part1Ptr);
+    if (part2Ptr) {
+	Tcl_DecrRefCount(part2Ptr);
+    }
+
+    return resPtr;
+}
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * Tcl_ObjGetVar2 --
+ *
+ *	Return the value of a Tcl variable as a Tcl object, given a two-part
+ *	name consisting of array name and element within array.
+ *
+ * Results:
+ *	The return value points to the current object value of the variable
+ *	given by part1Ptr and part2Ptr. If the specified variable doesn't
+ *	exist, or if there is a clash in array usage, then NULL is returned
+ *	and a message will be left in the interpreter's result if the
+ *	TCL_LEAVE_ERR_MSG flag is set.
+ *
+ * Side effects:
+ *	The ref count for the returned object is _not_ incremented to reflect
+ *	the returned reference; if you want to keep a reference to the object
+ *	you must increment its ref count yourself.
+ *
+ *	Callers must incr part2Ptr if they plan to decr it.
+ *
+ *----------------------------------------------------------------------
+ */
+
+Tcl_Obj *
+Tcl_ObjGetVar2(
+    Tcl_Interp *interp,		/* Command interpreter in which variable is to
+				 * be looked up. */
+    register Tcl_Obj *part1Ptr,	/* Points to an object holding the name of an
+				 * array (if part2 is non-NULL) or the name of
+				 * a variable. */
+    register Tcl_Obj *part2Ptr,	/* If non-null, points to an object holding
+				 * the name of an element in the array
+				 * part1Ptr. */
+    int flags)			/* OR-ed combination of TCL_GLOBAL_ONLY and
+				 * TCL_LEAVE_ERR_MSG bits. */
+{
+    Var *varPtr, *arrayPtr;
+
+    /*
+     * Filter to pass through only the flags this interface supports.
+     */
+
+    flags &= (TCL_GLOBAL_ONLY|TCL_NAMESPACE_ONLY|TCL_LEAVE_ERR_MSG);
+    varPtr = TclObjLookupVarEx(interp, part1Ptr, part2Ptr, flags, "read",
+	    /*createPart1*/ 0, /*createPart2*/ 1, &arrayPtr);
+    if (varPtr == NULL) {
+	return NULL;
+    }
+
+    return TclPtrGetVarIdx(interp, varPtr, arrayPtr, part1Ptr, part2Ptr,
+	    flags, -1);
+}
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * TclPtrGetVar --
+ *
+ *	Return the value of a Tcl variable as a Tcl object, given the pointers
+ *	to the variable's (and possibly containing array's) VAR structure.
+ *
+ * Results:
+ *	The return value points to the current object value of the variable
+ *	given by varPtr. If the specified variable doesn't exist, or if there
+ *	is a clash in array usage, then NULL is returned and a message will be
+ *	left in the interpreter's result if the TCL_LEAVE_ERR_MSG flag is set.
+ *
+ * Side effects:
+ *	The ref count for the returned object is _not_ incremented to reflect
+ *	the returned reference; if you want to keep a reference to the object
+ *	you must increment its ref count yourself.
+ *
+ *----------------------------------------------------------------------
+ */
+
+Tcl_Obj *
+TclPtrGetVar(
+    Tcl_Interp *interp,		/* Command interpreter in which variable is to
+				 * be looked up. */
+    Tcl_Var varPtr,		/* The variable to be read.*/
+    Tcl_Var arrayPtr,		/* NULL for scalar variables, pointer to the
+				 * containing array otherwise. */
+    Tcl_Obj *part1Ptr,		/* Name of an array (if part2 is non-NULL) or
+				 * the name of a variable. */
+    Tcl_Obj *part2Ptr,		/* If non-NULL, gives the name of an element
+				 * in the array part1. */
+    const int flags)		/* OR-ed combination of TCL_GLOBAL_ONLY, and
+				 * TCL_LEAVE_ERR_MSG bits. */
+{
+    if (varPtr == NULL) {
+	Tcl_Panic("varPtr must not be NULL");
+    }
+    if (part1Ptr == NULL) {
+	Tcl_Panic("part1Ptr must not be NULL");
+    }
+    return TclPtrGetVarIdx(interp, (Var *) varPtr, (Var *) arrayPtr,
+	    part1Ptr, part2Ptr, flags, -1);
+}
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * TclPtrGetVarIdx --
+ *
+ *	Return the value of a Tcl variable as a Tcl object, given the pointers
+ *	to the variable's (and possibly containing array's) VAR structure.
+ *
+ * Results:
+ *	The return value points to the current object value of the variable
+ *	given by varPtr. If the specified variable doesn't exist, or if there
+ *	is a clash in array usage, then NULL is returned and a message will be
+ *	left in the interpreter's result if the TCL_LEAVE_ERR_MSG flag is set.
+ *
+ * Side effects:
+ *	The ref count for the returned object is _not_ incremented to reflect
+ *	the returned reference; if you want to keep a reference to the object
+ *	you must increment its ref count yourself.
+ *
+ *----------------------------------------------------------------------
+ */
+
+Tcl_Obj *
+TclPtrGetVarIdx(
+    Tcl_Interp *interp,		/* Command interpreter in which variable is to
+				 * be looked up. */
+    register Var *varPtr,	/* The variable to be read.*/
+    Var *arrayPtr,		/* NULL for scalar variables, pointer to the
+				 * containing array otherwise. */
+    Tcl_Obj *part1Ptr,		/* Name of an array (if part2 is non-NULL) or
+				 * the name of a variable. */
+    Tcl_Obj *part2Ptr,		/* If non-NULL, gives the name of an element
+				 * in the array part1. */
+    const int flags,		/* OR-ed combination of TCL_GLOBAL_ONLY, and
+				 * TCL_LEAVE_ERR_MSG bits. */
+    int index)			/* Index into the local variable table of the
+				 * variable, or -1. Only used when part1Ptr is
+				 * NULL. */
+{
+    Interp *iPtr = (Interp *) interp;
+    const char *msg;
+
+    /*
+     * Invoke any read traces that have been set for the variable.
+     */
+
+    if ((varPtr->flags & VAR_TRACED_READ)
+	    || (arrayPtr && (arrayPtr->flags & VAR_TRACED_READ))) {
+	if (TCL_ERROR == TclObjCallVarTraces(iPtr, arrayPtr, varPtr,
+		part1Ptr, part2Ptr,
+		(flags & (TCL_NAMESPACE_ONLY|TCL_GLOBAL_ONLY))
+		| TCL_TRACE_READS, (flags & TCL_LEAVE_ERR_MSG), index)) {
+	    goto errorReturn;
+	}
+    }
+
+    /*
+     * Return the element if it's an existing scalar variable.
+     */
+
+    if (TclIsVarScalar(varPtr) && !TclIsVarUndefined(varPtr)) {
+	return varPtr->value.objPtr;
+    }
+
+    if (flags & TCL_LEAVE_ERR_MSG) {
+	if (TclIsVarUndefined(varPtr) && arrayPtr
+		&& !TclIsVarUndefined(arrayPtr)) {
+	    msg = noSuchElement;
+	} else if (TclIsVarArray(varPtr)) {
+	    msg = isArray;
+	} else {
+	    msg = noSuchVar;
+	}
+	TclObjVarErrMsg(interp, part1Ptr, part2Ptr, "read", msg, index);
+    }
+
+    /*
+     * An error. If the variable doesn't exist anymore and no-one's using it,
+     * then free up the relevant structures and hash table entries.
+     */
+
+  errorReturn:
+    Tcl_SetErrorCode(interp, "TCL", "READ", "VARNAME", NULL);
+    if (TclIsVarUndefined(varPtr)) {
+	TclCleanupVar(varPtr, arrayPtr);
+    }
+    return NULL;
+}
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * Tcl_SetObjCmd --
+ *
+ *	This function is invoked to process the "set" Tcl command. See the
+ *	user documentation for details on what it does.
+ *
+ * Results:
+ *	A standard Tcl result value.
+ *
+ * Side effects:
+ *	A variable's value may be changed.
+ *
+ *----------------------------------------------------------------------
+ */
+
+	/* ARGSUSED */
+int
+Tcl_SetObjCmd(
+    ClientData dummy,		/* Not used. */
+    register Tcl_Interp *interp,/* Current interpreter. */
+    int objc,			/* Number of arguments. */
+    Tcl_Obj *const objv[])	/* Argument objects. */
+{
+    Tcl_Obj *varValueObj;
+
+    if (objc == 2) {
+	varValueObj = Tcl_ObjGetVar2(interp, objv[1], NULL,TCL_LEAVE_ERR_MSG);
+	if (varValueObj == NULL) {
+	    return TCL_ERROR;
+	}
+	Tcl_SetObjResult(interp, varValueObj);
+	return TCL_OK;
+    } else if (objc == 3) {
+	varValueObj = Tcl_ObjSetVar2(interp, objv[1], NULL, objv[2],
+		TCL_LEAVE_ERR_MSG);
+	if (varValueObj == NULL) {
+	    return TCL_ERROR;
+	}
+	Tcl_SetObjResult(interp, varValueObj);
+	return TCL_OK;
+    } else {
+	Tcl_WrongNumArgs(interp, 1, objv, "varName ?newValue?");
+	return TCL_ERROR;
+    }
+}
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * Tcl_SetVar --
+ *
+ *	Change the value of a variable.
+ *
+ * Results:
+ *	Returns a pointer to the malloc'ed string which is the character
+ *	representation of the variable's new value. The caller must not modify
+ *	this string. If the write operation was disallowed then NULL is
+ *	returned; if the TCL_LEAVE_ERR_MSG flag is set, then an explanatory
+ *	message will be left in the interp's result. Note that the returned
+ *	string may not be the same as newValue; this is because variable
+ *	traces may modify the variable's value.
+ *
+ * Side effects:
+ *	If varName is defined as a local or global variable in interp, its
+ *	value is changed to newValue. If varName isn't currently defined, then
+ *	a new global variable by that name is created.
+ *
+ *----------------------------------------------------------------------
+ */
+
+#undef Tcl_SetVar
+const char *
+Tcl_SetVar(
+    Tcl_Interp *interp,		/* Command interpreter in which varName is to
+				 * be looked up. */
+    const char *varName,	/* Name of a variable in interp. */
+    const char *newValue,	/* New value for varName. */
+    int flags)			/* Various flags that tell how to set value:
+				 * any of TCL_GLOBAL_ONLY, TCL_NAMESPACE_ONLY,
+				 * TCL_APPEND_VALUE, TCL_LIST_ELEMENT,
+				 * TCL_LEAVE_ERR_MSG. */
+{
+    Tcl_Obj *varValuePtr, *varNamePtr = Tcl_NewStringObj(varName, -1);
+
+    Tcl_IncrRefCount(varNamePtr);
+    varValuePtr = Tcl_ObjSetVar2(interp, varNamePtr, NULL,
+	    Tcl_NewStringObj(newValue, -1), flags);
+    Tcl_DecrRefCount(varNamePtr);
+
+    if (varValuePtr == NULL) {
+	return NULL;
+    }
+    return TclGetString(varValuePtr);
+}
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * Tcl_SetVar2 --
+ *
+ *	Given a two-part variable name, which may refer either to a scalar
+ *	variable or an element of an array, change the value of the variable.
+ *	If the named scalar or array or element doesn't exist then create one.
+ *
+ * Results:
+ *	Returns a pointer to the malloc'ed string which is the character
+ *	representation of the variable's new value. The caller must not modify
+ *	this string. If the write operation was disallowed because an array
+ *	was expected but not found (or vice versa), then NULL is returned; if
+ *	the TCL_LEAVE_ERR_MSG flag is set, then an explanatory message will be
+ *	left in the interp's result. Note that the returned string may not be
+ *	the same as newValue; this is because variable traces may modify the
+ *	variable's value.
+ *
+ * Side effects:
+ *	The value of the given variable is set. If either the array or the
+ *	entry didn't exist then a new one is created.
+ *
+ *----------------------------------------------------------------------
+ */
+
+const char *
+Tcl_SetVar2(
+    Tcl_Interp *interp,		/* Command interpreter in which variable is to
+				 * be looked up. */
+    const char *part1,		/* If part2 is NULL, this is name of scalar
+				 * variable. Otherwise it is the name of an
+				 * array. */
+    const char *part2,		/* Name of an element within an array, or
+				 * NULL. */
+    const char *newValue,	/* New value for variable. */
+    int flags)			/* Various flags that tell how to set value:
+				 * any of TCL_GLOBAL_ONLY, TCL_NAMESPACE_ONLY,
+				 * TCL_APPEND_VALUE, TCL_LIST_ELEMENT, or
+				 * TCL_LEAVE_ERR_MSG. */
+{
+    Tcl_Obj *varValuePtr = Tcl_SetVar2Ex(interp, part1, part2,
+	    Tcl_NewStringObj(newValue, -1), flags);
+
+    if (varValuePtr == NULL) {
+	return NULL;
+    }
+    return TclGetString(varValuePtr);
+}
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * Tcl_SetVar2Ex --
+ *
+ *	Given a two-part variable name, which may refer either to a scalar
+ *	variable or an element of an array, change the value of the variable
+ *	to a new Tcl object value. If the named scalar or array or element
+ *	doesn't exist then create one.
+ *
+ * Results:
+ *	Returns a pointer to the Tcl_Obj holding the new value of the
+ *	variable. If the write operation was disallowed because an array was
+ *	expected but not found (or vice versa), then NULL is returned; if the
+ *	TCL_LEAVE_ERR_MSG flag is set, then an explanatory message will be
+ *	left in the interpreter's result. Note that the returned object may
+ *	not be the same one referenced by newValuePtr; this is because
+ *	variable traces may modify the variable's value.
+ *
+ * Side effects:
+ *	The value of the given variable is set. If either the array or the
+ *	entry didn't exist then a new variable is created.
+ *
+ *	The reference count is decremented for any old value of the variable
+ *	and incremented for its new value. If the new value for the variable
+ *	is not the same one referenced by newValuePtr (perhaps as a result of
+ *	a variable trace), then newValuePtr's ref count is left unchanged by
+ *	Tcl_SetVar2Ex. newValuePtr's ref count is also left unchanged if we
+ *	are appending it as a string value: that is, if "flags" includes
+ *	TCL_APPEND_VALUE but not TCL_LIST_ELEMENT.
+ *
+ *	The reference count for the returned object is _not_ incremented: if
+ *	you want to keep a reference to the object you must increment its ref
+ *	count yourself.
+ *
+ *----------------------------------------------------------------------
+ */
+
+Tcl_Obj *
+Tcl_SetVar2Ex(
+    Tcl_Interp *interp,		/* Command interpreter in which variable is to
+				 * be found. */
+    const char *part1,		/* Name of an array (if part2 is non-NULL) or
+				 * the name of a variable. */
+    const char *part2,		/* If non-NULL, gives the name of an element
+				 * in the array part1. */
+    Tcl_Obj *newValuePtr,	/* New value for variable. */
+    int flags)			/* Various flags that tell how to set value:
+				 * any of TCL_GLOBAL_ONLY, TCL_NAMESPACE_ONLY,
+				 * TCL_APPEND_VALUE, TCL_LIST_ELEMENT or
+				 * TCL_LEAVE_ERR_MSG. */
+{
+    Tcl_Obj *resPtr, *part2Ptr = NULL, *part1Ptr = Tcl_NewStringObj(part1, -1);
+
+    Tcl_IncrRefCount(part1Ptr);
+    if (part2) {
+	part2Ptr = Tcl_NewStringObj(part2, -1);
+	Tcl_IncrRefCount(part2Ptr);
+    }
+
+    resPtr = Tcl_ObjSetVar2(interp, part1Ptr, part2Ptr, newValuePtr, flags);
+
+    Tcl_DecrRefCount(part1Ptr);
+    if (part2Ptr) {
+	Tcl_DecrRefCount(part2Ptr);
+    }
+
+    return resPtr;
+}
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * Tcl_ObjSetVar2 --
+ *
+ *	This function is the same as Tcl_SetVar2Ex above, except the variable
+ *	names are passed in Tcl object instead of strings.
+ *
+ * Results:
+ *	Returns a pointer to the Tcl_Obj holding the new value of the
+ *	variable. If the write operation was disallowed because an array was
+ *	expected but not found (or vice versa), then NULL is returned; if the
+ *	TCL_LEAVE_ERR_MSG flag is set, then an explanatory message will be
+ *	left in the interpreter's result. Note that the returned object may
+ *	not be the same one referenced by newValuePtr; this is because
+ *	variable traces may modify the variable's value.
+ *
+ * Side effects:
+ *	The value of the given variable is set. If either the array or the
+ *	entry didn't exist then a new variable is created.
+ *	Callers must Incr part1Ptr if they plan to Decr it.
+ *	Callers must Incr part2Ptr if they plan to Decr it.
+ *
+ *----------------------------------------------------------------------
+ */
+
+Tcl_Obj *
+Tcl_ObjSetVar2(
+    Tcl_Interp *interp,		/* Command interpreter in which variable is to
+				 * be found. */
+    register Tcl_Obj *part1Ptr,	/* Points to an object holding the name of an
+				 * array (if part2 is non-NULL) or the name of
+				 * a variable. */
+    register Tcl_Obj *part2Ptr,	/* If non-NULL, points to an object holding
+				 * the name of an element in the array
+				 * part1Ptr. */
+    Tcl_Obj *newValuePtr,	/* New value for variable. */
+    int flags)			/* Various flags that tell how to set value:
+				 * any of TCL_GLOBAL_ONLY, TCL_NAMESPACE_ONLY,
+				 * TCL_APPEND_VALUE, TCL_LIST_ELEMENT, or
+				 * TCL_LEAVE_ERR_MSG. */
+{
+    Var *varPtr, *arrayPtr;
+
+    /*
+     * Filter to pass through only the flags this interface supports.
+     */
+
+    flags &= (TCL_GLOBAL_ONLY|TCL_NAMESPACE_ONLY|TCL_LEAVE_ERR_MSG
+	    |TCL_APPEND_VALUE|TCL_LIST_ELEMENT);
+    varPtr = TclObjLookupVarEx(interp, part1Ptr, part2Ptr, flags, "set",
+	    /*createPart1*/ 1, /*createPart2*/ 1, &arrayPtr);
+    if (varPtr == NULL) {
+	if (newValuePtr->refCount == 0) {
+	    Tcl_DecrRefCount(newValuePtr);
+	}
+	return NULL;
+    }
+
+    return TclPtrSetVarIdx(interp, varPtr, arrayPtr, part1Ptr, part2Ptr,
+	    newValuePtr, flags, -1);
+}
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * TclPtrSetVar --
+ *
+ *	This function is the same as Tcl_SetVar2Ex above, except that it
+ *	requires pointers to the variable's Var structs in addition to the
+ *	variable names.
+ *
+ * Results:
+ *	Returns a pointer to the Tcl_Obj holding the new value of the
+ *	variable. If the write operation was disallowed because an array was
+ *	expected but not found (or vice versa), then NULL is returned; if the
+ *	TCL_LEAVE_ERR_MSG flag is set, then an explanatory message will be
+ *	left in the interpreter's result. Note that the returned object may
+ *	not be the same one referenced by newValuePtr; this is because
+ *	variable traces may modify the variable's value.
+ *
+ * Side effects:
+ *	The value of the given variable is set. If either the array or the
+ *	entry didn't exist then a new variable is created.
+ *
+ *----------------------------------------------------------------------
+ */
+
+Tcl_Obj *
+TclPtrSetVar(
+    Tcl_Interp *interp,		/* Command interpreter in which variable is to
+				 * be looked up. */
+    Tcl_Var varPtr,		/* Reference to the variable to set. */
+    Tcl_Var arrayPtr,		/* Reference to the array containing the
+				 * variable, or NULL if the variable is a
+				 * scalar. */
+    Tcl_Obj *part1Ptr,		/* Name of an array (if part2 is non-NULL) or
+				 * the name of a variable. */
+    Tcl_Obj *part2Ptr,		/* If non-NULL, gives the name of an element
+				 * in the array part1. */
+    Tcl_Obj *newValuePtr,	/* New value for variable. */
+    const int flags)		/* OR-ed combination of TCL_GLOBAL_ONLY, and
+				 * TCL_LEAVE_ERR_MSG bits. */
+{
+    if (varPtr == NULL) {
+	Tcl_Panic("varPtr must not be NULL");
+    }
+    if (part1Ptr == NULL) {
+	Tcl_Panic("part1Ptr must not be NULL");
+    }
+    if (newValuePtr == NULL) {
+	Tcl_Panic("newValuePtr must not be NULL");
+    }
+    return TclPtrSetVarIdx(interp, (Var *) varPtr, (Var *) arrayPtr,
+	    part1Ptr, part2Ptr, newValuePtr, flags, -1);
+}
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * TclPtrSetVarIdx --
+ *
+ *	This function is the same as Tcl_SetVar2Ex above, except that it
+ *	requires pointers to the variable's Var structs in addition to the
+ *	variable names.
+ *
+ * Results:
+ *	Returns a pointer to the Tcl_Obj holding the new value of the
+ *	variable. If the write operation was disallowed because an array was
+ *	expected but not found (or vice versa), then NULL is returned; if the
+ *	TCL_LEAVE_ERR_MSG flag is set, then an explanatory message will be
+ *	left in the interpreter's result. Note that the returned object may
+ *	not be the same one referenced by newValuePtr; this is because
+ *	variable traces may modify the variable's value.
+ *
+ * Side effects:
+ *	The value of the given variable is set. If either the array or the
+ *	entry didn't exist then a new variable is created.
+ *
+ *----------------------------------------------------------------------
+ */
+
+Tcl_Obj *
+TclPtrSetVarIdx(
+    Tcl_Interp *interp,		/* Command interpreter in which variable is to
+				 * be looked up. */
+    register Var *varPtr,	/* Reference to the variable to set. */
+    Var *arrayPtr,		/* Reference to the array containing the
+				 * variable, or NULL if the variable is a
+				 * scalar. */
+    Tcl_Obj *part1Ptr,		/* Name of an array (if part2 is non-NULL) or
+				 * the name of a variable. NULL if the 'index'
+				 * parameter is >= 0 */
+    Tcl_Obj *part2Ptr,		/* If non-NULL, gives the name of an element
+				 * in the array part1. */
+    Tcl_Obj *newValuePtr,	/* New value for variable. */
+    const int flags,		/* OR-ed combination of TCL_GLOBAL_ONLY, and
+				 * TCL_LEAVE_ERR_MSG bits. */
+    int index)			/* Index of local var where part1 is to be
+				 * found. */
+{
+    Interp *iPtr = (Interp *) interp;
+    Tcl_Obj *oldValuePtr;
+    Tcl_Obj *resultPtr = NULL;
+    int result;
+    int cleanupOnEarlyError = (newValuePtr->refCount == 0);
+
+    /*
+     * If the variable is in a hashtable and its hPtr field is NULL, then we
+     * may have an upvar to an array element where the array was deleted or an
+     * upvar to a namespace variable whose namespace was deleted. Generate an
+     * error (allowing the variable to be reset would screw up our storage
+     * allocation and is meaningless anyway).
+     */
+
+    if (TclIsVarDeadHash(varPtr)) {
+	if (flags & TCL_LEAVE_ERR_MSG) {
+	    if (TclIsVarArrayElement(varPtr)) {
+		TclObjVarErrMsg(interp, part1Ptr, part2Ptr, "set",
+			danglingElement, index);
+		Tcl_SetErrorCode(interp, "TCL", "LOOKUP", "ELEMENT", NULL);
+	    } else {
+		TclObjVarErrMsg(interp, part1Ptr, part2Ptr, "set",
+			danglingVar, index);
+		Tcl_SetErrorCode(interp, "TCL", "LOOKUP", "VARNAME", NULL);
+	    }
+	}
+	goto earlyError;
+    }
+
+    /*
+     * It's an error to try to set an array variable itself.
+     */
+
+    if (TclIsVarArray(varPtr)) {
+	if (flags & TCL_LEAVE_ERR_MSG) {
+	    TclObjVarErrMsg(interp, part1Ptr, part2Ptr, "set", isArray,index);
+	    Tcl_SetErrorCode(interp, "TCL", "WRITE", "ARRAY", NULL);
+	}
+	goto earlyError;
+    }
+
+    /*
+     * Invoke any read traces that have been set for the variable if it is
+     * requested. This was done for INST_LAPPEND_* but that was inconsistent
+     * with the non-bc instruction, and would cause failures trying to
+     * lappend to any non-existing ::env var, which is inconsistent with
+     * documented behavior. [Bug #3057639].
+     */
+
+    if ((flags & TCL_TRACE_READS) && ((varPtr->flags & VAR_TRACED_READ)
+	    || (arrayPtr && (arrayPtr->flags & VAR_TRACED_READ)))) {
+	if (TCL_ERROR == TclObjCallVarTraces(iPtr, arrayPtr, varPtr,
+		part1Ptr, part2Ptr,
+		TCL_TRACE_READS, (flags & TCL_LEAVE_ERR_MSG), index)) {
+	    goto earlyError;
+	}
+    }
+
+    /*
+     * Set the variable's new value. If appending, append the new value to the
+     * variable, either as a list element or as a string. Also, if appending,
+     * then if the variable's old value is unshared we can modify it directly,
+     * otherwise we must create a new copy to modify: this is "copy on write".
+     */
+
+    oldValuePtr = varPtr->value.objPtr;
+    if (flags & TCL_LIST_ELEMENT && !(flags & TCL_APPEND_VALUE)) {
+	varPtr->value.objPtr = NULL;
+    }
+    if (flags & (TCL_APPEND_VALUE|TCL_LIST_ELEMENT)) {
+	if (flags & TCL_LIST_ELEMENT) {		/* Append list element. */
+	    if (oldValuePtr == NULL) {
+		TclNewObj(oldValuePtr);
+		varPtr->value.objPtr = oldValuePtr;
+		Tcl_IncrRefCount(oldValuePtr);	/* Since var is referenced. */
+	    } else if (Tcl_IsShared(oldValuePtr)) {
+		varPtr->value.objPtr = Tcl_DuplicateObj(oldValuePtr);
+		TclDecrRefCount(oldValuePtr);
+		oldValuePtr = varPtr->value.objPtr;
+		Tcl_IncrRefCount(oldValuePtr);	/* Since var is referenced. */
+	    }
+	    result = Tcl_ListObjAppendElement(interp, oldValuePtr,
+		    newValuePtr);
+	    if (result != TCL_OK) {
+		goto earlyError;
+	    }
+	} else {				/* Append string. */
+	    /*
+	     * We append newValuePtr's bytes but don't change its ref count.
+	     */
+
+	    if (oldValuePtr == NULL) {
+		varPtr->value.objPtr = newValuePtr;
+		Tcl_IncrRefCount(newValuePtr);
+	    } else {
+		if (Tcl_IsShared(oldValuePtr)) {	/* Append to copy. */
+		    varPtr->value.objPtr = Tcl_DuplicateObj(oldValuePtr);
+
+		    TclContinuationsCopy(varPtr->value.objPtr, oldValuePtr);
+
+		    TclDecrRefCount(oldValuePtr);
+		    oldValuePtr = varPtr->value.objPtr;
+		    Tcl_IncrRefCount(oldValuePtr);	/* Since var is ref */
+		}
+		Tcl_AppendObjToObj(oldValuePtr, newValuePtr);
+		if (newValuePtr->refCount == 0) {
+		    Tcl_DecrRefCount(newValuePtr);
+		}
+	    }
+	}
+    } else if (newValuePtr != oldValuePtr) {
+	/*
+	 * In this case we are replacing the value, so we don't need to do
+	 * more than swap the objects.
+	 */
+
+	varPtr->value.objPtr = newValuePtr;
+	Tcl_IncrRefCount(newValuePtr);		/* Var is another ref. */
+	if (oldValuePtr != NULL) {
+	    TclDecrRefCount(oldValuePtr);	/* Discard old value. */
+	}
+    }
+
+    /*
+     * Invoke any write traces for the variable.
+     */
+
+    if ((varPtr->flags & VAR_TRACED_WRITE)
+	    || (arrayPtr && (arrayPtr->flags & VAR_TRACED_WRITE))) {
+	if (TCL_ERROR == TclObjCallVarTraces(iPtr, arrayPtr, varPtr, part1Ptr,
+		part2Ptr, (flags & (TCL_GLOBAL_ONLY|TCL_NAMESPACE_ONLY))
+		| TCL_TRACE_WRITES, (flags & TCL_LEAVE_ERR_MSG), index)) {
+	    goto cleanup;
+	}
+    }
+
+    /*
+     * Return the variable's value unless the variable was changed in some
+     * gross way by a trace (e.g. it was unset and then recreated as an
+     * array).
+     */
+
+    if (TclIsVarScalar(varPtr) && !TclIsVarUndefined(varPtr)) {
+	return varPtr->value.objPtr;
+    }
+
+    /*
+     * A trace changed the value in some gross way. Return an empty string
+     * object.
+     */
+
+    resultPtr = iPtr->emptyObjPtr;
+
+    /*
+     * If the variable doesn't exist anymore and no-one's using it, then free
+     * up the relevant structures and hash table entries.
+     */
+
+  cleanup:
+    if (resultPtr == NULL) {
+	Tcl_SetErrorCode(interp, "TCL", "WRITE", "VARNAME", NULL);
+    }
+    if (TclIsVarUndefined(varPtr)) {
+	TclCleanupVar(varPtr, arrayPtr);
+    }
+    return resultPtr;
+
+  earlyError:
+    if (cleanupOnEarlyError) {
+	Tcl_DecrRefCount(newValuePtr);
+    }
+    goto cleanup;
+}
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * TclIncrObjVar2 --
+ *
+ *	Given a two-part variable name, which may refer either to a scalar
+ *	variable or an element of an array, increment the Tcl object value of
+ *	the variable by a specified Tcl_Obj increment value.
+ *
+ * Results:
+ *	Returns a pointer to the Tcl_Obj holding the new value of the
+ *	variable. If the specified variable doesn't exist, or there is a clash
+ *	in array usage, or an error occurs while executing variable traces,
+ *	then NULL is returned and a message will be left in the interpreter's
+ *	result.
+ *
+ * Side effects:
+ *	The value of the given variable is incremented by the specified
+ *	amount. If either the array or the entry didn't exist then a new
+ *	variable is created. The ref count for the returned object is _not_
+ *	incremented to reflect the returned reference; if you want to keep a
+ *	reference to the object you must increment its ref count yourself.
+ *	Callers must Incr part1Ptr if they plan to Decr it.
+ *	Callers must Incr part2Ptr if they plan to Decr it.
+ *
+ *----------------------------------------------------------------------
+ */
+
+Tcl_Obj *
+TclIncrObjVar2(
+    Tcl_Interp *interp,		/* Command interpreter in which variable is to
+				 * be found. */
+    Tcl_Obj *part1Ptr,		/* Points to an object holding the name of an
+				 * array (if part2 is non-NULL) or the name of
+				 * a variable. */
+    Tcl_Obj *part2Ptr,		/* If non-null, points to an object holding
+				 * the name of an element in the array
+				 * part1Ptr. */
+    Tcl_Obj *incrPtr,		/* Amount to be added to variable. */
+    int flags)			/* Various flags that tell how to incr value:
+				 * any of TCL_GLOBAL_ONLY, TCL_NAMESPACE_ONLY,
+				 * TCL_APPEND_VALUE, TCL_LIST_ELEMENT,
+				 * TCL_LEAVE_ERR_MSG. */
+{
+    Var *varPtr, *arrayPtr;
+
+    varPtr = TclObjLookupVarEx(interp, part1Ptr, part2Ptr, flags, "read",
+	    1, 1, &arrayPtr);
+    if (varPtr == NULL) {
+	Tcl_AddErrorInfo(interp,
+		"\n    (reading value of variable to increment)");
+	return NULL;
+    }
+    return TclPtrIncrObjVarIdx(interp, varPtr, arrayPtr, part1Ptr, part2Ptr,
+	    incrPtr, flags, -1);
+}
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * TclPtrIncrObjVar --
+ *
+ *	Given the pointers to a variable and possible containing array,
+ *	increment the Tcl object value of the variable by a Tcl_Obj increment.
+ *
+ * Results:
+ *	Returns a pointer to the Tcl_Obj holding the new value of the
+ *	variable. If the specified variable doesn't exist, or there is a clash
+ *	in array usage, or an error occurs while executing variable traces,
+ *	then NULL is returned and a message will be left in the interpreter's
+ *	result.
+ *
+ * Side effects:
+ *	The value of the given variable is incremented by the specified
+ *	amount. If either the array or the entry didn't exist then a new
+ *	variable is created. The ref count for the returned object is _not_
+ *	incremented to reflect the returned reference; if you want to keep a
+ *	reference to the object you must increment its ref count yourself.
+ *
+ *----------------------------------------------------------------------
+ */
+
+Tcl_Obj *
+TclPtrIncrObjVar(
+    Tcl_Interp *interp,		/* Command interpreter in which variable is to
+				 * be found. */
+    Tcl_Var varPtr,		/* Reference to the variable to set. */
+    Tcl_Var arrayPtr,		/* Reference to the array containing the
+				 * variable, or NULL if the variable is a
+				 * scalar. */
+    Tcl_Obj *part1Ptr,		/* Points to an object holding the name of an
+				 * array (if part2 is non-NULL) or the name of
+				 * a variable. */
+    Tcl_Obj *part2Ptr,		/* If non-null, points to an object holding
+				 * the name of an element in the array
+				 * part1Ptr. */
+    Tcl_Obj *incrPtr,		/* Increment value. */
+/* TODO: Which of these flag values really make sense? */
+    const int flags)		/* Various flags that tell how to incr value:
+				 * any of TCL_GLOBAL_ONLY, TCL_NAMESPACE_ONLY,
+				 * TCL_APPEND_VALUE, TCL_LIST_ELEMENT,
+				 * TCL_LEAVE_ERR_MSG. */
+{
+    if (varPtr == NULL) {
+	Tcl_Panic("varPtr must not be NULL");
+    }
+    if (part1Ptr == NULL) {
+	Tcl_Panic("part1Ptr must not be NULL");
+    }
+    return TclPtrIncrObjVarIdx(interp, (Var *) varPtr, (Var *) arrayPtr,
+	    part1Ptr, part2Ptr, incrPtr, flags, -1);
+}
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * TclPtrIncrObjVarIdx --
+ *
+ *	Given the pointers to a variable and possible containing array,
+ *	increment the Tcl object value of the variable by a Tcl_Obj increment.
+ *
+ * Results:
+ *	Returns a pointer to the Tcl_Obj holding the new value of the
+ *	variable. If the specified variable doesn't exist, or there is a clash
+ *	in array usage, or an error occurs while executing variable traces,
+ *	then NULL is returned and a message will be left in the interpreter's
+ *	result.
+ *
+ * Side effects:
+ *	The value of the given variable is incremented by the specified
+ *	amount. If either the array or the entry didn't exist then a new
+ *	variable is created. The ref count for the returned object is _not_
+ *	incremented to reflect the returned reference; if you want to keep a
+ *	reference to the object you must increment its ref count yourself.
+ *
+ *----------------------------------------------------------------------
+ */
+
+Tcl_Obj *
+TclPtrIncrObjVarIdx(
+    Tcl_Interp *interp,		/* Command interpreter in which variable is to
+				 * be found. */
+    Var *varPtr,		/* Reference to the variable to set. */
+    Var *arrayPtr,		/* Reference to the array containing the
+				 * variable, or NULL if the variable is a
+				 * scalar. */
+    Tcl_Obj *part1Ptr,		/* Points to an object holding the name of an
+				 * array (if part2 is non-NULL) or the name of
+				 * a variable. */
+    Tcl_Obj *part2Ptr,		/* If non-null, points to an object holding
+				 * the name of an element in the array
+				 * part1Ptr. */
+    Tcl_Obj *incrPtr,		/* Increment value. */
+/* TODO: Which of these flag values really make sense? */
+    const int flags,		/* Various flags that tell how to incr value:
+				 * any of TCL_GLOBAL_ONLY, TCL_NAMESPACE_ONLY,
+				 * TCL_APPEND_VALUE, TCL_LIST_ELEMENT,
+				 * TCL_LEAVE_ERR_MSG. */
+    int index)			/* Index into the local variable table of the
+				 * variable, or -1. Only used when part1Ptr is
+				 * NULL. */
+{
+    register Tcl_Obj *varValuePtr;
+
+    if (TclIsVarInHash(varPtr)) {
+	VarHashRefCount(varPtr)++;
+    }
+    varValuePtr = TclPtrGetVarIdx(interp, varPtr, arrayPtr, part1Ptr,
+	    part2Ptr, flags, index);
+    if (TclIsVarInHash(varPtr)) {
+	VarHashRefCount(varPtr)--;
+    }
+    if (varValuePtr == NULL) {
+	varValuePtr = Tcl_NewIntObj(0);
+    }
+    if (Tcl_IsShared(varValuePtr)) {
+	/* Copy on write */
+	varValuePtr = Tcl_DuplicateObj(varValuePtr);
+
+	if (TCL_OK == TclIncrObj(interp, varValuePtr, incrPtr)) {
+	    return TclPtrSetVarIdx(interp, varPtr, arrayPtr, part1Ptr,
+		    part2Ptr, varValuePtr, flags, index);
+	} else {
+	    Tcl_DecrRefCount(varValuePtr);
+	    return NULL;
+	}
+    } else {
+	/* Unshared - can Incr in place */
+	if (TCL_OK == TclIncrObj(interp, varValuePtr, incrPtr)) {
+
+	    /*
+	     * This seems dumb to write the incremeted value into the var
+	     * after we just adjusted the value in place, but the spec for
+	     * [incr] requires that write traces fire, and making this call
+	     * is the way to make that happen.
+	     */
+
+	    return TclPtrSetVarIdx(interp, varPtr, arrayPtr, part1Ptr,
+		    part2Ptr, varValuePtr, flags, index);
+	} else {
+	    return NULL;
+	}
+    }
+}
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * Tcl_UnsetVar --
+ *
+ *	Delete a variable, so that it may not be accessed anymore.
+ *
+ * Results:
+ *	Returns TCL_OK if the variable was successfully deleted, TCL_ERROR if
+ *	the variable can't be unset. In the event of an error, if the
+ *	TCL_LEAVE_ERR_MSG flag is set then an error message is left in the
+ *	interp's result.
+ *
+ * Side effects:
+ *	If varName is defined as a local or global variable in interp, it is
+ *	deleted.
+ *
+ *----------------------------------------------------------------------
+ */
+
+#undef Tcl_UnsetVar
+int
+Tcl_UnsetVar(
+    Tcl_Interp *interp,		/* Command interpreter in which varName is to
+				 * be looked up. */
+    const char *varName,	/* Name of a variable in interp. May be either
+				 * a scalar name or an array name or an
+				 * element in an array. */
+    int flags)			/* OR-ed combination of any of
+				 * TCL_GLOBAL_ONLY, TCL_NAMESPACE_ONLY or
+				 * TCL_LEAVE_ERR_MSG. */
+{
+    int result;
+    Tcl_Obj *varNamePtr;
+
+    varNamePtr = Tcl_NewStringObj(varName, -1);
+    Tcl_IncrRefCount(varNamePtr);
+
+    /*
+     * Filter to pass through only the flags this interface supports.
+     */
+
+    flags &= (TCL_GLOBAL_ONLY|TCL_NAMESPACE_ONLY|TCL_LEAVE_ERR_MSG);
+    result = TclObjUnsetVar2(interp, varNamePtr, NULL, flags);
+
+    Tcl_DecrRefCount(varNamePtr);
+    return result;
+}
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * Tcl_UnsetVar2 --
+ *
+ *	Delete a variable, given a 2-part name.
+ *
+ * Results:
+ *	Returns TCL_OK if the variable was successfully deleted, TCL_ERROR if
+ *	the variable can't be unset. In the event of an error, if the
+ *	TCL_LEAVE_ERR_MSG flag is set then an error message is left in the
+ *	interp's result.
+ *
+ * Side effects:
+ *	If part1 and part2 indicate a local or global variable in interp, it
+ *	is deleted. If part1 is an array name and part2 is NULL, then the
+ *	whole array is deleted.
+ *
+ *----------------------------------------------------------------------
+ */
+
+int
+Tcl_UnsetVar2(
+    Tcl_Interp *interp,		/* Command interpreter in which varName is to
+				 * be looked up. */
+    const char *part1,		/* Name of variable or array. */
+    const char *part2,		/* Name of element within array or NULL. */
+    int flags)			/* OR-ed combination of any of
+				 * TCL_GLOBAL_ONLY, TCL_NAMESPACE_ONLY,
+				 * TCL_LEAVE_ERR_MSG. */
+{
+    int result;
+    Tcl_Obj *part2Ptr = NULL, *part1Ptr = Tcl_NewStringObj(part1, -1);
+
+    if (part2) {
+	part2Ptr = Tcl_NewStringObj(part2, -1);
+    }
+
+    /*
+     * Filter to pass through only the flags this interface supports.
+     */
+
+    flags &= (TCL_GLOBAL_ONLY|TCL_NAMESPACE_ONLY|TCL_LEAVE_ERR_MSG);
+    result = TclObjUnsetVar2(interp, part1Ptr, part2Ptr, flags);
+
+    Tcl_DecrRefCount(part1Ptr);
+    if (part2Ptr) {
+	Tcl_DecrRefCount(part2Ptr);
+    }
+    return result;
+}
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * TclObjUnsetVar2 --
+ *
+ *	Delete a variable, given a 2-object name.
+ *
+ * Results:
+ *	Returns TCL_OK if the variable was successfully deleted, TCL_ERROR if
+ *	the variable can't be unset. In the event of an error, if the
+ *	TCL_LEAVE_ERR_MSG flag is set then an error message is left in the
+ *	interp's result.
+ *
+ * Side effects:
+ *	If part1ptr and part2Ptr indicate a local or global variable in
+ *	interp, it is deleted. If part1Ptr is an array name and part2Ptr is
+ *	NULL, then the whole array is deleted.
+ *
+ *----------------------------------------------------------------------
+ */
+
+int
+TclObjUnsetVar2(
+    Tcl_Interp *interp,		/* Command interpreter in which varName is to
+				 * be looked up. */
+    Tcl_Obj *part1Ptr,		/* Name of variable or array. */
+    Tcl_Obj *part2Ptr,		/* Name of element within array or NULL. */
+    int flags)			/* OR-ed combination of any of
+				 * TCL_GLOBAL_ONLY, TCL_NAMESPACE_ONLY,
+				 * TCL_LEAVE_ERR_MSG. */
+{
+    Var *varPtr, *arrayPtr;
+
+    varPtr = TclObjLookupVarEx(interp, part1Ptr, part2Ptr, flags, "unset",
+	    /*createPart1*/ 0, /*createPart2*/ 0, &arrayPtr);
+    if (varPtr == NULL) {
+	return TCL_ERROR;
+    }
+
+    return TclPtrUnsetVarIdx(interp, varPtr, arrayPtr, part1Ptr, part2Ptr,
+	    flags, -1);
+}
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * TclPtrUnsetVar --
+ *
+ *	Delete a variable, given the pointers to the variable's (and possibly
+ *	containing array's) VAR structure.
+ *
+ * Results:
+ *	Returns TCL_OK if the variable was successfully deleted, TCL_ERROR if
+ *	the variable can't be unset. In the event of an error, if the
+ *	TCL_LEAVE_ERR_MSG flag is set then an error message is left in the
+ *	interp's result.
+ *
+ * Side effects:
+ *	If varPtr and arrayPtr indicate a local or global variable in interp,
+ *	it is deleted. If varPtr is an array reference and part2Ptr is NULL,
+ *	then the whole array is deleted.
+ *
+ *----------------------------------------------------------------------
+ */
+
+int
+TclPtrUnsetVar(
+    Tcl_Interp *interp,		/* Command interpreter in which varName is to
+				 * be looked up. */
+    Tcl_Var varPtr,		/* The variable to be unset. */
+    Tcl_Var arrayPtr,		/* NULL for scalar variables, pointer to the
+				 * containing array otherwise. */
+    Tcl_Obj *part1Ptr,		/* Name of an array (if part2 is non-NULL) or
+				 * the name of a variable. */
+    Tcl_Obj *part2Ptr,		/* If non-NULL, gives the name of an element
+				 * in the array part1. */
+    const int flags)		/* OR-ed combination of any of
+				 * TCL_GLOBAL_ONLY, TCL_NAMESPACE_ONLY,
+				 * TCL_LEAVE_ERR_MSG. */
+{
+    if (varPtr == NULL) {
+	Tcl_Panic("varPtr must not be NULL");
+    }
+    if (part1Ptr == NULL) {
+	Tcl_Panic("part1Ptr must not be NULL");
+    }
+    return TclPtrUnsetVarIdx(interp, (Var *) varPtr, (Var *) arrayPtr,
+	    part1Ptr, part2Ptr, flags, -1);
+}
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * TclPtrUnsetVarIdx --
+ *
+ *	Delete a variable, given the pointers to the variable's (and possibly
+ *	containing array's) VAR structure.
+ *
+ * Results:
+ *	Returns TCL_OK if the variable was successfully deleted, TCL_ERROR if
+ *	the variable can't be unset. In the event of an error, if the
+ *	TCL_LEAVE_ERR_MSG flag is set then an error message is left in the
+ *	interp's result.
+ *
+ * Side effects:
+ *	If varPtr and arrayPtr indicate a local or global variable in interp,
+ *	it is deleted. If varPtr is an array reference and part2Ptr is NULL,
+ *	then the whole array is deleted.
+ *
+ *----------------------------------------------------------------------
+ */
+
+int
+TclPtrUnsetVarIdx(
+    Tcl_Interp *interp,		/* Command interpreter in which varName is to
+				 * be looked up. */
+    register Var *varPtr,	/* The variable to be unset. */
+    Var *arrayPtr,		/* NULL for scalar variables, pointer to the
+				 * containing array otherwise. */
+    Tcl_Obj *part1Ptr,		/* Name of an array (if part2 is non-NULL) or
+				 * the name of a variable. */
+    Tcl_Obj *part2Ptr,		/* If non-NULL, gives the name of an element
+				 * in the array part1. */
+    const int flags,		/* OR-ed combination of any of
+				 * TCL_GLOBAL_ONLY, TCL_NAMESPACE_ONLY,
+				 * TCL_LEAVE_ERR_MSG. */
+    int index)			/* Index into the local variable table of the
+				 * variable, or -1. Only used when part1Ptr is
+				 * NULL. */
+{
+    Interp *iPtr = (Interp *) interp;
+    int result = (TclIsVarUndefined(varPtr)? TCL_ERROR : TCL_OK);
+
+    /*
+     * Keep the variable alive until we're done with it. We used to
+     * increase/decrease the refCount for each operation, making it hard to
+     * find [Bug 735335] - caused by unsetting the variable whose value was
+     * the variable's name.
+     */
+
+    if (TclIsVarInHash(varPtr)) {
+	VarHashRefCount(varPtr)++;
+    }
+
+    UnsetVarStruct(varPtr, arrayPtr, iPtr, part1Ptr, part2Ptr, flags, index);
+
+    /*
+     * It's an error to unset an undefined variable.
+     */
+
+    if (result != TCL_OK) {
+	if (flags & TCL_LEAVE_ERR_MSG) {
+	    TclObjVarErrMsg(interp, part1Ptr, part2Ptr, "unset",
+		    ((arrayPtr == NULL) ? noSuchVar : noSuchElement), index);
+	    Tcl_SetErrorCode(interp, "TCL", "UNSET", "VARNAME", NULL);
+	}
+    }
+
+    /*
+     * Finally, if the variable is truly not in use then free up its Var
+     * structure and remove it from its hash table, if any. The ref count of
+     * its value object, if any, was decremented above.
+     */
+
+    if (TclIsVarInHash(varPtr)) {
+	VarHashRefCount(varPtr)--;
+	CleanupVar(varPtr, arrayPtr);
+    }
+    return result;
+}
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * UnsetVarStruct --
+ *
+ *	Unset and delete a variable. This does the internal work for
+ *	TclObjUnsetVar2 and TclDeleteNamespaceVars, which call here for each
+ *	variable to be unset and deleted.
+ *
+ * Results:
+ *	None.
+ *
+ * Side effects:
+ *	If the arguments indicate a local or global variable in iPtr, it is
+ *	unset and deleted.
+ *
+ *----------------------------------------------------------------------
+ */
+
+static void
+UnsetVarStruct(
+    Var *varPtr,
+    Var *arrayPtr,
+    Interp *iPtr,
+    Tcl_Obj *part1Ptr,
+    Tcl_Obj *part2Ptr,
+    int flags,
+    int index)
+{
+    Var dummyVar;
+    int traced = TclIsVarTraced(varPtr)
+	    || (arrayPtr && (arrayPtr->flags & VAR_TRACED_UNSET));
+
+    if (arrayPtr && (arrayPtr->flags & VAR_SEARCH_ACTIVE)) {
+	DeleteSearches(iPtr, arrayPtr);
+    } else if (varPtr->flags & VAR_SEARCH_ACTIVE) {
+	DeleteSearches(iPtr, varPtr);
+    }
+
+    /*
+     * The code below is tricky, because of the possibility that a trace
+     * function might try to access a variable being deleted. To handle this
+     * situation gracefully, do things in three steps:
+     * 1. Copy the contents of the variable to a dummy variable structure, and
+     *    mark the original Var structure as undefined.
+     * 2. Invoke traces and clean up the variable, using the dummy copy.
+     * 3. If at the end of this the original variable is still undefined and
+     *    has no outstanding references, then delete it (but it could have
+     *    gotten recreated by a trace).
+     */
+
+    dummyVar = *varPtr;
+    dummyVar.flags &= ~VAR_ALL_HASH;
+    TclSetVarUndefined(varPtr);
+
+    /*
+     * Call trace functions for the variable being deleted. Then delete its
+     * traces. Be sure to abort any other traces for the variable that are
+     * still pending. Special tricks:
+     * 1. We need to increment varPtr's refCount around this: TclCallVarTraces
+     *    will use dummyVar so it won't increment varPtr's refCount itself.
+     * 2. Turn off the VAR_TRACE_ACTIVE flag in dummyVar: we want to call
+     *    unset traces even if other traces are pending.
+     */
+
+    if (traced) {
+	VarTrace *tracePtr = NULL;
+	Tcl_HashEntry *tPtr;
+
+	if (TclIsVarTraced(&dummyVar)) {
+	    /*
+	     * Transfer any existing traces on var, IF there are unset traces.
+	     * Otherwise just delete them.
+	     */
+
+	    int isNew;
+
+	    tPtr = Tcl_FindHashEntry(&iPtr->varTraces, varPtr);
+	    tracePtr = Tcl_GetHashValue(tPtr);
+	    varPtr->flags &= ~VAR_ALL_TRACES;
+	    Tcl_DeleteHashEntry(tPtr);
+	    if (dummyVar.flags & VAR_TRACED_UNSET) {
+		tPtr = Tcl_CreateHashEntry(&iPtr->varTraces,
+			&dummyVar, &isNew);
+		Tcl_SetHashValue(tPtr, tracePtr);
+	    }
+	}
+
+	if ((dummyVar.flags & VAR_TRACED_UNSET)
+		|| (arrayPtr && (arrayPtr->flags & VAR_TRACED_UNSET))) {
+	    dummyVar.flags &= ~VAR_TRACE_ACTIVE;
+	    TclObjCallVarTraces(iPtr, arrayPtr, &dummyVar, part1Ptr, part2Ptr,
+		    (flags & (TCL_GLOBAL_ONLY|TCL_NAMESPACE_ONLY))
+			    | TCL_TRACE_UNSETS,
+		    /* leaveErrMsg */ 0, index);
+
+	    /*
+	     * The traces that we just called may have triggered a change in
+	     * the set of traces. If so, reload the traces to manipulate.
+	     */
+
+	    tracePtr = NULL;
+	    if (TclIsVarTraced(&dummyVar)) {
+		tPtr = Tcl_FindHashEntry(&iPtr->varTraces, &dummyVar);
+		if (tPtr) {
+		    tracePtr = Tcl_GetHashValue(tPtr);
+		    Tcl_DeleteHashEntry(tPtr);
+		}
+	    }
+	}
+
+	if (tracePtr) {
+	    ActiveVarTrace *activePtr;
+
+	    while (tracePtr) {
+		VarTrace *prevPtr = tracePtr;
+
+		tracePtr = tracePtr->nextPtr;
+		prevPtr->nextPtr = NULL;
+		Tcl_EventuallyFree(prevPtr, TCL_DYNAMIC);
+	    }
+	    for (activePtr = iPtr->activeVarTracePtr;  activePtr != NULL;
+		    activePtr = activePtr->nextPtr) {
+		if (activePtr->varPtr == varPtr) {
+		    activePtr->nextTracePtr = NULL;
+		}
+	    }
+	    dummyVar.flags &= ~VAR_ALL_TRACES;
+	}
+    }
+
+    if (TclIsVarScalar(&dummyVar) && (dummyVar.value.objPtr != NULL)) {
+	/*
+	 * Decrement the ref count of the var's value.
+	 */
+
+	Tcl_Obj *objPtr = dummyVar.value.objPtr;
+
+	TclDecrRefCount(objPtr);
+    } else if (TclIsVarArray(&dummyVar)) {
+	/*
+	 * If the variable is an array, delete all of its elements. This must
+	 * be done after calling and deleting the traces on the array, above
+	 * (that's the way traces are defined). If the array name is not
+	 * present and is required for a trace on some element, it will be
+	 * computed at DeleteArray.
+	 */
+
+	DeleteArray(iPtr, part1Ptr, (Var *) &dummyVar, (flags
+		& (TCL_GLOBAL_ONLY|TCL_NAMESPACE_ONLY)) | TCL_TRACE_UNSETS,
+		index);
+    } else if (TclIsVarLink(&dummyVar)) {
+	/*
+	 * For global/upvar variables referenced in procedures, decrement the
+	 * reference count on the variable referred to, and free the
+	 * referenced variable if it's no longer needed.
+	 */
+
+	Var *linkPtr = dummyVar.value.linkPtr;
+
+	if (TclIsVarInHash(linkPtr)) {
+	    VarHashRefCount(linkPtr)--;
+	    CleanupVar(linkPtr, NULL);
+	}
+    }
+
+    /*
+     * If the variable was a namespace variable, decrement its reference
+     * count.
+     */
+
+    TclClearVarNamespaceVar(varPtr);
+}
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * Tcl_UnsetObjCmd --
+ *
+ *	This object-based function is invoked to process the "unset" Tcl
+ *	command. See the user documentation for details on what it does.
+ *
+ * Results:
+ *	A standard Tcl object result value.
+ *
+ * Side effects:
+ *	See the user documentation.
+ *
+ *----------------------------------------------------------------------
+ */
+
+	/* ARGSUSED */
+int
+Tcl_UnsetObjCmd(
+    ClientData dummy,		/* Not used. */
+    Tcl_Interp *interp,		/* Current interpreter. */
+    int objc,			/* Number of arguments. */
+    Tcl_Obj *const objv[])	/* Argument objects. */
+{
+    register int i, flags = TCL_LEAVE_ERR_MSG;
+    register const char *name;
+
+    if (objc == 1) {
+	/*
+	 * Do nothing if no arguments supplied, so as to match command
+	 * documentation.
+	 */
+
+	return TCL_OK;
+    }
+
+    /*
+     * Simple, restrictive argument parsing. The only options are -- and
+     * -nocomplain (which must come first and be given exactly to be an
+     * option).
+     */
+
+    i = 1;
+    name = TclGetString(objv[i]);
+    if (name[0] == '-') {
+	if (strcmp("-nocomplain", name) == 0) {
+	    i++;
+	    if (i == objc) {
+		return TCL_OK;
+	    }
+	    flags = 0;
+	    name = TclGetString(objv[i]);
+	}
+	if (strcmp("--", name) == 0) {
+	    i++;
+	}
+    }
+
+    for (; i < objc; i++) {
+	if ((TclObjUnsetVar2(interp, objv[i], NULL, flags) != TCL_OK)
+		&& (flags == TCL_LEAVE_ERR_MSG)) {
+	    return TCL_ERROR;
+	}
+    }
+    return TCL_OK;
+}
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * Tcl_AppendObjCmd --
+ *
+ *	This object-based function is invoked to process the "append" Tcl
+ *	command. See the user documentation for details on what it does.
+ *
+ * Results:
+ *	A standard Tcl object result value.
+ *
+ * Side effects:
+ *	A variable's value may be changed.
+ *
+ *----------------------------------------------------------------------
+ */
+
+	/* ARGSUSED */
+int
+Tcl_AppendObjCmd(
+    ClientData dummy,		/* Not used. */
+    Tcl_Interp *interp,		/* Current interpreter. */
+    int objc,			/* Number of arguments. */
+    Tcl_Obj *const objv[])	/* Argument objects. */
+{
+    Var *varPtr, *arrayPtr;
+    register Tcl_Obj *varValuePtr = NULL;
+				/* Initialized to avoid compiler warning. */
+    int i;
+
+    if (objc < 2) {
+	Tcl_WrongNumArgs(interp, 1, objv, "varName ?value ...?");
+	return TCL_ERROR;
+    }
+
+    if (objc == 2) {
+	varValuePtr = Tcl_ObjGetVar2(interp, objv[1], NULL,TCL_LEAVE_ERR_MSG);
+	if (varValuePtr == NULL) {
+	    return TCL_ERROR;
+	}
+    } else {
+	varPtr = TclObjLookupVarEx(interp, objv[1], NULL, TCL_LEAVE_ERR_MSG,
+		"set", /*createPart1*/ 1, /*createPart2*/ 1, &arrayPtr);
+	if (varPtr == NULL) {
+	    return TCL_ERROR;
+	}
+	for (i=2 ; i<objc ; i++) {
+	    /*
+	     * Note that we do not need to increase the refCount of the Var
+	     * pointers: should a trace delete the variable, the return value
+	     * of TclPtrSetVarIdx will be NULL or emptyObjPtr, and we will not
+	     * access the variable again.
+	     */
+
+	    varValuePtr = TclPtrSetVarIdx(interp, varPtr, arrayPtr, objv[1],
+		    NULL, objv[i], TCL_APPEND_VALUE|TCL_LEAVE_ERR_MSG, -1);
+	    if ((varValuePtr == NULL) ||
+		    (varValuePtr == ((Interp *) interp)->emptyObjPtr)) {
+		return TCL_ERROR;
+	    }
+	}
+    }
+    Tcl_SetObjResult(interp, varValuePtr);
+    return TCL_OK;
+}
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * Tcl_LappendObjCmd --
+ *
+ *	This object-based function is invoked to process the "lappend" Tcl
+ *	command. See the user documentation for details on what it does.
+ *
+ * Results:
+ *	A standard Tcl object result value.
+ *
+ * Side effects:
+ *	A variable's value may be changed.
+ *
+ *----------------------------------------------------------------------
+ */
+
+	/* ARGSUSED */
+int
+Tcl_LappendObjCmd(
+    ClientData dummy,		/* Not used. */
+    Tcl_Interp *interp,		/* Current interpreter. */
+    int objc,			/* Number of arguments. */
+    Tcl_Obj *const objv[])	/* Argument objects. */
+{
+    Tcl_Obj *varValuePtr, *newValuePtr;
+    int numElems, createdNewObj;
+    Var *varPtr, *arrayPtr;
+    int result;
+
+    if (objc < 2) {
+	Tcl_WrongNumArgs(interp, 1, objv, "varName ?value ...?");
+	return TCL_ERROR;
+    }
+    if (objc == 2) {
+	newValuePtr = Tcl_ObjGetVar2(interp, objv[1], NULL, 0);
+	if (newValuePtr == NULL) {
+	    /*
+	     * The variable doesn't exist yet. Just create it with an empty
+	     * initial value.
+	     */
+
+	    TclNewObj(varValuePtr);
+	    newValuePtr = Tcl_ObjSetVar2(interp, objv[1], NULL, varValuePtr,
+		    TCL_LEAVE_ERR_MSG);
+	    if (newValuePtr == NULL) {
+		return TCL_ERROR;
+	    }
+	} else {
+	    result = TclListObjLength(interp, newValuePtr, &numElems);
+	    if (result != TCL_OK) {
+		return result;
+	    }
+	}
+    } else {
+	/*
+	 * We have arguments to append. We used to call Tcl_SetVar2 to append
+	 * each argument one at a time to ensure that traces were run for each
+	 * append step. We now append the arguments all at once because it's
+	 * faster. Note that a read trace and a write trace for the variable
+	 * will now each only be called once. Also, if the variable's old
+	 * value is unshared we modify it directly, otherwise we create a new
+	 * copy to modify: this is "copy on write".
+	 */
+
+	createdNewObj = 0;
+
+	/*
+	 * Protect the variable pointers around the TclPtrGetVarIdx call
+	 * to insure that they remain valid even if the variable was undefined
+	 * and unused.
+	 */
+
+	varPtr = TclObjLookupVarEx(interp, objv[1], NULL, TCL_LEAVE_ERR_MSG,
+		"set", /*createPart1*/ 1, /*createPart2*/ 1, &arrayPtr);
+	if (varPtr == NULL) {
+	    return TCL_ERROR;
+	}
+	if (TclIsVarInHash(varPtr)) {
+	    VarHashRefCount(varPtr)++;
+	}
+	if (arrayPtr && TclIsVarInHash(arrayPtr)) {
+	    VarHashRefCount(arrayPtr)++;
+	}
+	varValuePtr = TclPtrGetVarIdx(interp, varPtr, arrayPtr, objv[1], NULL,
+		TCL_LEAVE_ERR_MSG, -1);
+	if (TclIsVarInHash(varPtr)) {
+	    VarHashRefCount(varPtr)--;
+	}
+	if (arrayPtr && TclIsVarInHash(arrayPtr)) {
+	    VarHashRefCount(arrayPtr)--;
+	}
+
+	if (varValuePtr == NULL) {
+	    /*
+	     * We couldn't read the old value: either the var doesn't yet
+	     * exist or it's an array element. If it's new, we will try to
+	     * create it with Tcl_ObjSetVar2 below.
+	     */
+
+	    TclNewObj(varValuePtr);
+	    createdNewObj = 1;
+	} else if (Tcl_IsShared(varValuePtr)) {
+	    varValuePtr = Tcl_DuplicateObj(varValuePtr);
+	    createdNewObj = 1;
+	}
+
+	result = TclListObjLength(interp, varValuePtr, &numElems);
+	if (result == TCL_OK) {
+	    result = Tcl_ListObjReplace(interp, varValuePtr, numElems, 0,
+		    (objc-2), (objv+2));
+	}
+	if (result != TCL_OK) {
+	    if (createdNewObj) {
+		TclDecrRefCount(varValuePtr); /* Free unneeded obj. */
+	    }
+	    return result;
+	}
+
+	/*
+	 * Now store the list object back into the variable. If there is an
+	 * error setting the new value, decrement its ref count if it was new
+	 * and we didn't create the variable.
+	 */
+
+	newValuePtr = TclPtrSetVarIdx(interp, varPtr, arrayPtr, objv[1], NULL,
+		varValuePtr, TCL_LEAVE_ERR_MSG, -1);
+	if (newValuePtr == NULL) {
+	    return TCL_ERROR;
+	}
+    }
+
+    /*
+     * Set the interpreter's object result to refer to the variable's value
+     * object.
+     */
+
+    Tcl_SetObjResult(interp, newValuePtr);
+    return TCL_OK;
+}
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * TclArraySet --
+ *
+ *	Set the elements of an array. If there are no elements to set, create
+ *	an empty array. This routine is used by the Tcl_ArrayObjCmd and by the
+ *	TclSetupEnv routine.
+ *
+ * Results:
+ *	A standard Tcl result object.
+ *
+ * Side effects:
+ *	A variable will be created if one does not already exist.
+ *	Callers must Incr arrayNameObj if they pland to Decr it.
+ *
+ *----------------------------------------------------------------------
+ */
+
+int
+TclArraySet(
+    Tcl_Interp *interp,		/* Current interpreter. */
+    Tcl_Obj *arrayNameObj,	/* The array name. */
+    Tcl_Obj *arrayElemObj)	/* The array elements list or dict. If this is
+				 * NULL, create an empty array. */
+{
+    Var *varPtr, *arrayPtr;
+    int result, i;
+
+    varPtr = TclObjLookupVarEx(interp, arrayNameObj, NULL,
+	    /*flags*/ TCL_LEAVE_ERR_MSG, /*msg*/ "set", /*createPart1*/ 1,
+	    /*createPart2*/ 1, &arrayPtr);
+    if (varPtr == NULL) {
+	return TCL_ERROR;
+    }
+    if (arrayPtr) {
+	CleanupVar(varPtr, arrayPtr);
+	TclObjVarErrMsg(interp, arrayNameObj, NULL, "set", needArray, -1);
+	Tcl_SetErrorCode(interp, "TCL", "LOOKUP", "VARNAME",
+		TclGetString(arrayNameObj), NULL);
+	return TCL_ERROR;
+    }
+
+    if (arrayElemObj == NULL) {
+	goto ensureArray;
+    }
+
+    /*
+     * Install the contents of the dictionary or list into the array.
+     */
+
+    if (arrayElemObj->typePtr == &tclDictType) {
+	Tcl_Obj *keyPtr, *valuePtr;
+	Tcl_DictSearch search;
+	int done;
+
+	if (Tcl_DictObjSize(interp, arrayElemObj, &done) != TCL_OK) {
+	    return TCL_ERROR;
+	}
+	if (done == 0) {
+	    /*
+	     * Empty, so we'll just force the array to be properly existing
+	     * instead.
+	     */
+
+	    goto ensureArray;
+	}
+
+	/*
+	 * Don't need to look at result of Tcl_DictObjFirst as we've just
+	 * successfully used a dictionary operation on the same object.
+	 */
+
+	for (Tcl_DictObjFirst(interp, arrayElemObj, &search,
+		&keyPtr, &valuePtr, &done) ; !done ;
+		Tcl_DictObjNext(&search, &keyPtr, &valuePtr, &done)) {
+	    /*
+	     * At this point, it would be nice if the key was directly usable
+	     * by the array. This isn't the case though.
+	     */
+
+	    Var *elemVarPtr = TclLookupArrayElement(interp, arrayNameObj,
+		    keyPtr, TCL_LEAVE_ERR_MSG, "set", 1, 1, varPtr, -1);
+
+	    if ((elemVarPtr == NULL) ||
+		    (TclPtrSetVarIdx(interp, elemVarPtr, varPtr, arrayNameObj,
+		    keyPtr, valuePtr, TCL_LEAVE_ERR_MSG, -1) == NULL)) {
+		Tcl_DictObjDone(&search);
+		return TCL_ERROR;
+	    }
+	}
+	return TCL_OK;
+    } else {
+	/*
+	 * Not a dictionary, so assume (and convert to, for backward-
+	 * -compatibility reasons) a list.
+	 */
+
+	int elemLen;
+	Tcl_Obj **elemPtrs, *copyListObj;
+
+	result = TclListObjGetElements(interp, arrayElemObj,
+		&elemLen, &elemPtrs);
+	if (result != TCL_OK) {
+	    return result;
+	}
+	if (elemLen & 1) {
+	    Tcl_SetObjResult(interp, Tcl_NewStringObj(
+		    "list must have an even number of elements", -1));
+	    Tcl_SetErrorCode(interp, "TCL", "ARGUMENT", "FORMAT", NULL);
+	    return TCL_ERROR;
+	}
+	if (elemLen == 0) {
+	    goto ensureArray;
+	}
+
+	/*
+	 * We needn't worry about traces invalidating arrayPtr: should that be
+	 * the case, TclPtrSetVarIdx will return NULL so that we break out of
+	 * the loop and return an error.
+	 */
+
+	copyListObj = TclListObjCopy(NULL, arrayElemObj);
+	for (i=0 ; i<elemLen ; i+=2) {
+	    Var *elemVarPtr = TclLookupArrayElement(interp, arrayNameObj,
+		    elemPtrs[i], TCL_LEAVE_ERR_MSG, "set", 1, 1, varPtr, -1);
+
+	    if ((elemVarPtr == NULL) ||
+		    (TclPtrSetVarIdx(interp, elemVarPtr, varPtr, arrayNameObj,
+		    elemPtrs[i],elemPtrs[i+1],TCL_LEAVE_ERR_MSG,-1) == NULL)){
+		result = TCL_ERROR;
+		break;
+	    }
+	}
+	Tcl_DecrRefCount(copyListObj);
+	return result;
+    }
+
+    /*
+     * The list is empty make sure we have an array, or create one if
+     * necessary.
+     */
+
+  ensureArray:
+    if (varPtr != NULL) {
+	if (TclIsVarArray(varPtr)) {
+	    /*
+	     * Already an array, done.
+	     */
+
+	    return TCL_OK;
+	}
+	if (TclIsVarArrayElement(varPtr) || !TclIsVarUndefined(varPtr)) {
+	    /*
+	     * Either an array element, or a scalar: lose!
+	     */
+
+	    TclObjVarErrMsg(interp, arrayNameObj, NULL, "array set",
+		    needArray, -1);
+	    Tcl_SetErrorCode(interp, "TCL", "WRITE", "ARRAY", NULL);
+	    return TCL_ERROR;
+	}
+    }
+    TclSetVarArray(varPtr);
+    varPtr->value.tablePtr = ckalloc(sizeof(TclVarHashTable));
+    TclInitVarHashTable(varPtr->value.tablePtr, TclGetVarNsPtr(varPtr));
+    return TCL_OK;
+}
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * ArrayStartSearchCmd --
+ *
+ *	This object-based function is invoked to process the "array
+ *	startsearch" Tcl command. See the user documentation for details on
+ *	what it does.
+ *
+ * Results:
+ *	A standard Tcl result object.
+ *
+ * Side effects:
+ *	See the user documentation.
+ *
+ *----------------------------------------------------------------------
+ */
+
+	/* ARGSUSED */
+static int
+ArrayStartSearchCmd(
+    ClientData clientData,
+    Tcl_Interp *interp,
+    int objc,
+    Tcl_Obj *const objv[])
+{
+    Interp *iPtr = (Interp *) interp;
+    Var *varPtr, *arrayPtr;
+    Tcl_HashEntry *hPtr;
+    Tcl_Obj *varNameObj;
+    int isNew;
+    ArraySearch *searchPtr;
+    const char *varName;
+
+    if (objc != 2) {
+	Tcl_WrongNumArgs(interp, 1, objv, "arrayName");
+	return TCL_ERROR;
+    }
+    varNameObj = objv[1];
+
+    /*
+     * Locate the array variable.
+     */
+
+    varPtr = TclObjLookupVarEx(interp, varNameObj, NULL, /*flags*/ 0,
+	    /*msg*/ 0, /*createPart1*/ 0, /*createPart2*/ 0, &arrayPtr);
+    varName = TclGetString(varNameObj);
+
+    /*
+     * Special array trace used to keep the env array in sync for array names,
+     * array get, etc.
+     */
+
+    if (varPtr && (varPtr->flags & VAR_TRACED_ARRAY)
+	    && (TclIsVarArray(varPtr) || TclIsVarUndefined(varPtr))) {
+	if (TclObjCallVarTraces(iPtr, arrayPtr, varPtr, varNameObj, NULL,
+		(TCL_LEAVE_ERR_MSG|TCL_NAMESPACE_ONLY|TCL_GLOBAL_ONLY|
+		TCL_TRACE_ARRAY), /* leaveErrMsg */ 1, -1) == TCL_ERROR) {
+	    return TCL_ERROR;
+	}
+    }
+
+    /*
+     * Verify that it is indeed an array variable. This test comes after the
+     * traces - the variable may actually become an array as an effect of said
+     * traces.
+     */
+
+    if ((varPtr == NULL) || !TclIsVarArray(varPtr)
+	    || TclIsVarUndefined(varPtr)) {
+	Tcl_SetObjResult(interp, Tcl_ObjPrintf(
+		"\"%s\" isn't an array", varName));
+	Tcl_SetErrorCode(interp, "TCL", "LOOKUP", "ARRAY", varName, NULL);
+	return TCL_ERROR;
+    }
+
+    /*
+     * Make a new array search with a free name.
+     */
+
+    searchPtr = ckalloc(sizeof(ArraySearch));
+    hPtr = Tcl_CreateHashEntry(&iPtr->varSearches, varPtr, &isNew);
+    if (isNew) {
+	searchPtr->id = 1;
+	varPtr->flags |= VAR_SEARCH_ACTIVE;
+	searchPtr->nextPtr = NULL;
+    } else {
+	searchPtr->id = ((ArraySearch *) Tcl_GetHashValue(hPtr))->id + 1;
+	searchPtr->nextPtr = Tcl_GetHashValue(hPtr);
+    }
+    searchPtr->varPtr = varPtr;
+    searchPtr->nextEntry = VarHashFirstEntry(varPtr->value.tablePtr,
+	    &searchPtr->search);
+    Tcl_SetHashValue(hPtr, searchPtr);
+    Tcl_SetObjResult(interp,
+	    Tcl_ObjPrintf("s-%d-%s", searchPtr->id, varName));
+    return TCL_OK;
+}
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * ArrayAnyMoreCmd --
+ *
+ *	This object-based function is invoked to process the "array anymore"
+ *	Tcl command. See the user documentation for details on what it does.
+ *
+ * Results:
+ *	A standard Tcl result object.
+ *
+ * Side effects:
+ *	See the user documentation.
+ *
+ *----------------------------------------------------------------------
+ */
+
+	/* ARGSUSED */
+static int
+ArrayAnyMoreCmd(
+    ClientData clientData,
+    Tcl_Interp *interp,
+    int objc,
+    Tcl_Obj *const objv[])
+{
+    Interp *iPtr = (Interp *) interp;
+    Var *varPtr, *arrayPtr;
+    Tcl_Obj *varNameObj, *searchObj;
+    int gotValue;
+    ArraySearch *searchPtr;
+
+    if (objc != 3) {
+	Tcl_WrongNumArgs(interp, 1, objv, "arrayName searchId");
+	return TCL_ERROR;
+    }
+    varNameObj = objv[1];
+    searchObj = objv[2];
+
+    /*
+     * Locate the array variable.
+     */
+
+    varPtr = TclObjLookupVarEx(interp, varNameObj, NULL, /*flags*/ 0,
+	    /*msg*/ 0, /*createPart1*/ 0, /*createPart2*/ 0, &arrayPtr);
+
+    /*
+     * Special array trace used to keep the env array in sync for array names,
+     * array get, etc.
+     */
+
+    if (varPtr && (varPtr->flags & VAR_TRACED_ARRAY)
+	    && (TclIsVarArray(varPtr) || TclIsVarUndefined(varPtr))) {
+	if (TclObjCallVarTraces(iPtr, arrayPtr, varPtr, varNameObj, NULL,
+		(TCL_LEAVE_ERR_MSG|TCL_NAMESPACE_ONLY|TCL_GLOBAL_ONLY|
+		TCL_TRACE_ARRAY), /* leaveErrMsg */ 1, -1) == TCL_ERROR) {
+	    return TCL_ERROR;
+	}
+    }
+
+    /*
+     * Verify that it is indeed an array variable. This test comes after the
+     * traces - the variable may actually become an array as an effect of said
+     * traces.
+     */
+
+    if ((varPtr == NULL) || !TclIsVarArray(varPtr)
+	    || TclIsVarUndefined(varPtr)) {
+	Tcl_SetObjResult(interp, Tcl_ObjPrintf(
+		"\"%s\" isn't an array", TclGetString(varNameObj)));
+	Tcl_SetErrorCode(interp, "TCL", "LOOKUP", "ARRAY",
+		TclGetString(varNameObj), NULL);
+	return TCL_ERROR;
+    }
+
+    /*
+     * Get the search.
+     */
+
+    searchPtr = ParseSearchId(interp, varPtr, varNameObj, searchObj);
+    if (searchPtr == NULL) {
+	return TCL_ERROR;
+    }
+
+    /*
+     * Scan forward to find if there are any further elements in the array
+     * that are defined.
+     */
+
+    while (1) {
+	if (searchPtr->nextEntry != NULL) {
+	    varPtr = VarHashGetValue(searchPtr->nextEntry);
+	    if (!TclIsVarUndefined(varPtr)) {
+		gotValue = 1;
+		break;
+	    }
+	}
+	searchPtr->nextEntry = Tcl_NextHashEntry(&searchPtr->search);
+	if (searchPtr->nextEntry == NULL) {
+	    gotValue = 0;
+	    break;
+	}
+    }
+    Tcl_SetObjResult(interp, iPtr->execEnvPtr->constants[gotValue]);
+    return TCL_OK;
+}
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * ArrayNextElementCmd --
+ *
+ *	This object-based function is invoked to process the "array
+ *	nextelement" Tcl command. See the user documentation for details on
+ *	what it does.
+ *
+ * Results:
+ *	A standard Tcl result object.
+ *
+ * Side effects:
+ *	See the user documentation.
+ *
+ *----------------------------------------------------------------------
+ */
+
+	/* ARGSUSED */
+static int
+ArrayNextElementCmd(
+    ClientData clientData,
+    Tcl_Interp *interp,
+    int objc,
+    Tcl_Obj *const objv[])
+{
+    Interp *iPtr = (Interp *) interp;
+    Var *varPtr, *arrayPtr;
+    Tcl_Obj *varNameObj, *searchObj;
+    ArraySearch *searchPtr;
+
+    if (objc != 3) {
+	Tcl_WrongNumArgs(interp, 1, objv, "arrayName searchId");
+	return TCL_ERROR;
+    }
+    varNameObj = objv[1];
+    searchObj = objv[2];
+
+    /*
+     * Locate the array variable.
+     */
+
+    varPtr = TclObjLookupVarEx(interp, varNameObj, NULL, /*flags*/ 0,
+	    /*msg*/ 0, /*createPart1*/ 0, /*createPart2*/ 0, &arrayPtr);
+
+    /*
+     * Special array trace used to keep the env array in sync for array names,
+     * array get, etc.
+     */
+
+    if (varPtr && (varPtr->flags & VAR_TRACED_ARRAY)
+	    && (TclIsVarArray(varPtr) || TclIsVarUndefined(varPtr))) {
+	if (TclObjCallVarTraces(iPtr, arrayPtr, varPtr, varNameObj, NULL,
+		(TCL_LEAVE_ERR_MSG|TCL_NAMESPACE_ONLY|TCL_GLOBAL_ONLY|
+		TCL_TRACE_ARRAY), /* leaveErrMsg */ 1, -1) == TCL_ERROR) {
+	    return TCL_ERROR;
+	}
+    }
+
+    /*
+     * Verify that it is indeed an array variable. This test comes after the
+     * traces - the variable may actually become an array as an effect of said
+     * traces.
+     */
+
+    if ((varPtr == NULL) || !TclIsVarArray(varPtr)
+	    || TclIsVarUndefined(varPtr)) {
+	Tcl_SetObjResult(interp, Tcl_ObjPrintf(
+		"\"%s\" isn't an array", TclGetString(varNameObj)));
+	Tcl_SetErrorCode(interp, "TCL", "LOOKUP", "ARRAY",
+		TclGetString(varNameObj), NULL);
+	return TCL_ERROR;
+    }
+
+    /*
+     * Get the search.
+     */
+
+    searchPtr = ParseSearchId(interp, varPtr, varNameObj, searchObj);
+    if (searchPtr == NULL) {
+	return TCL_ERROR;
+    }
+
+    /*
+     * Get the next element from the search, or the empty string on
+     * exhaustion. Note that the [array anymore] command may well have already
+     * pulled a value from the hash enumeration, so we have to check the cache
+     * there first.
+     */
+
+    while (1) {
+	Tcl_HashEntry *hPtr = searchPtr->nextEntry;
+
+	if (hPtr == NULL) {
+	    hPtr = Tcl_NextHashEntry(&searchPtr->search);
+	    if (hPtr == NULL) {
+		return TCL_OK;
+	    }
+	} else {
+	    searchPtr->nextEntry = NULL;
+	}
+	varPtr = VarHashGetValue(hPtr);
+	if (!TclIsVarUndefined(varPtr)) {
+	    Tcl_SetObjResult(interp, VarHashGetKey(varPtr));
+	    return TCL_OK;
+	}
+    }
+}
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * ArrayDoneSearchCmd --
+ *
+ *	This object-based function is invoked to process the "array
+ *	donesearch" Tcl command. See the user documentation for details on
+ *	what it does.
+ *
+ * Results:
+ *	A standard Tcl result object.
+ *
+ * Side effects:
+ *	See the user documentation.
+ *
+ *----------------------------------------------------------------------
+ */
+
+	/* ARGSUSED */
+static int
+ArrayDoneSearchCmd(
+    ClientData clientData,
+    Tcl_Interp *interp,
+    int objc,
+    Tcl_Obj *const objv[])
+{
+    Interp *iPtr = (Interp *) interp;
+    Var *varPtr, *arrayPtr;
+    Tcl_HashEntry *hPtr;
+    Tcl_Obj *varNameObj, *searchObj;
+    ArraySearch *searchPtr, *prevPtr;
+
+    if (objc != 3) {
+	Tcl_WrongNumArgs(interp, 1, objv, "arrayName searchId");
+	return TCL_ERROR;
+    }
+    varNameObj = objv[1];
+    searchObj = objv[2];
+
+    /*
+     * Locate the array variable.
+     */
+
+    varPtr = TclObjLookupVarEx(interp, varNameObj, NULL, /*flags*/ 0,
+	    /*msg*/ 0, /*createPart1*/ 0, /*createPart2*/ 0, &arrayPtr);
+
+    /*
+     * Special array trace used to keep the env array in sync for array names,
+     * array get, etc.
+     */
+
+    if (varPtr && (varPtr->flags & VAR_TRACED_ARRAY)
+	    && (TclIsVarArray(varPtr) || TclIsVarUndefined(varPtr))) {
+	if (TclObjCallVarTraces(iPtr, arrayPtr, varPtr, varNameObj, NULL,
+		(TCL_LEAVE_ERR_MSG|TCL_NAMESPACE_ONLY|TCL_GLOBAL_ONLY|
+		TCL_TRACE_ARRAY), /* leaveErrMsg */ 1, -1) == TCL_ERROR) {
+	    return TCL_ERROR;
+	}
+    }
+
+    /*
+     * Verify that it is indeed an array variable. This test comes after the
+     * traces - the variable may actually become an array as an effect of said
+     * traces.
+     */
+
+    if ((varPtr == NULL) || !TclIsVarArray(varPtr)
+	    || TclIsVarUndefined(varPtr)) {
+	Tcl_SetObjResult(interp, Tcl_ObjPrintf(
+		"\"%s\" isn't an array", TclGetString(varNameObj)));
+	Tcl_SetErrorCode(interp, "TCL", "LOOKUP", "ARRAY",
+		TclGetString(varNameObj), NULL);
+	return TCL_ERROR;
+    }
+
+    /*
+     * Get the search.
+     */
+
+    searchPtr = ParseSearchId(interp, varPtr, varNameObj, searchObj);
+    if (searchPtr == NULL) {
+	return TCL_ERROR;
+    }
+
+    /*
+     * Unhook the search from the list of searches associated with the
+     * variable.
+     */
+
+    hPtr = Tcl_FindHashEntry(&iPtr->varSearches, varPtr);
+    if (searchPtr == Tcl_GetHashValue(hPtr)) {
+	if (searchPtr->nextPtr) {
+	    Tcl_SetHashValue(hPtr, searchPtr->nextPtr);
+	} else {
+	    varPtr->flags &= ~VAR_SEARCH_ACTIVE;
+	    Tcl_DeleteHashEntry(hPtr);
+	}
+    } else {
+	for (prevPtr=Tcl_GetHashValue(hPtr) ;; prevPtr=prevPtr->nextPtr) {
+	    if (prevPtr->nextPtr == searchPtr) {
+		prevPtr->nextPtr = searchPtr->nextPtr;
+		break;
+	    }
+	}
+    }
+    ckfree(searchPtr);
+    return TCL_OK;
+}
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * ArrayExistsCmd --
+ *
+ *	This object-based function is invoked to process the "array exists"
+ *	Tcl command. See the user documentation for details on what it does.
+ *
+ * Results:
+ *	A standard Tcl result object.
+ *
+ * Side effects:
+ *	See the user documentation.
+ *
+ *----------------------------------------------------------------------
+ */
+
+	/* ARGSUSED */
+static int
+ArrayExistsCmd(
+    ClientData clientData,
+    Tcl_Interp *interp,
+    int objc,
+    Tcl_Obj *const objv[])
+{
+    Interp *iPtr = (Interp *) interp;
+    Var *varPtr, *arrayPtr;
+    Tcl_Obj *arrayNameObj;
+    int notArray;
+
+    if (objc != 2) {
+	Tcl_WrongNumArgs(interp, 1, objv, "arrayName");
+	return TCL_ERROR;
+    }
+    arrayNameObj = objv[1];
+
+    /*
+     * Locate the array variable.
+     */
+
+    varPtr = TclObjLookupVarEx(interp, arrayNameObj, NULL, /*flags*/ 0,
+	    /*msg*/ 0, /*createPart1*/ 0, /*createPart2*/ 0, &arrayPtr);
+
+    /*
+     * Special array trace used to keep the env array in sync for array names,
+     * array get, etc.
+     */
+
+    if (varPtr && (varPtr->flags & VAR_TRACED_ARRAY)
+	    && (TclIsVarArray(varPtr) || TclIsVarUndefined(varPtr))) {
+	if (TclObjCallVarTraces(iPtr, arrayPtr, varPtr, arrayNameObj, NULL,
+		(TCL_LEAVE_ERR_MSG|TCL_NAMESPACE_ONLY|TCL_GLOBAL_ONLY|
+		TCL_TRACE_ARRAY), /* leaveErrMsg */ 1, -1) == TCL_ERROR) {
+	    return TCL_ERROR;
+	}
+    }
+
+    /*
+     * Check whether we've actually got an array variable.
+     */
+
+    notArray = ((varPtr == NULL) || !TclIsVarArray(varPtr)
+	    || TclIsVarUndefined(varPtr));
+    Tcl_SetObjResult(interp, iPtr->execEnvPtr->constants[!notArray]);
+    return TCL_OK;
+}
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * ArrayGetCmd --
+ *
+ *	This object-based function is invoked to process the "array get" Tcl
+ *	command. See the user documentation for details on what it does.
+ *
+ * Results:
+ *	A standard Tcl result object.
+ *
+ * Side effects:
+ *	See the user documentation.
+ *
+ *----------------------------------------------------------------------
+ */
+
+	/* ARGSUSED */
+static int
+ArrayGetCmd(
+    ClientData clientData,
+    Tcl_Interp *interp,
+    int objc,
+    Tcl_Obj *const objv[])
+{
+    Interp *iPtr = (Interp *) interp;
+    Var *varPtr, *arrayPtr, *varPtr2;
+    Tcl_Obj *varNameObj, *nameObj, *valueObj, *nameLstObj, *tmpResObj;
+    Tcl_Obj **nameObjPtr, *patternObj;
+    Tcl_HashSearch search;
+    const char *pattern;
+    int i, count, result;
+
+    switch (objc) {
+    case 2:
+	varNameObj = objv[1];
+	patternObj = NULL;
+	break;
+    case 3:
+	varNameObj = objv[1];
+	patternObj = objv[2];
+	break;
+    default:
+	Tcl_WrongNumArgs(interp, 1, objv, "arrayName ?pattern?");
+	return TCL_ERROR;
+    }
+
+    /*
+     * Locate the array variable.
+     */
+
+    varPtr = TclObjLookupVarEx(interp, varNameObj, NULL, /*flags*/ 0,
+	    /*msg*/ 0, /*createPart1*/ 0, /*createPart2*/ 0, &arrayPtr);
+
+    /*
+     * Special array trace used to keep the env array in sync for array names,
+     * array get, etc.
+     */
+
+    if (varPtr && (varPtr->flags & VAR_TRACED_ARRAY)
+	    && (TclIsVarArray(varPtr) || TclIsVarUndefined(varPtr))) {
+	if (TclObjCallVarTraces(iPtr, arrayPtr, varPtr, varNameObj, NULL,
+		(TCL_LEAVE_ERR_MSG|TCL_NAMESPACE_ONLY|TCL_GLOBAL_ONLY|
+		TCL_TRACE_ARRAY), /* leaveErrMsg */ 1, -1) == TCL_ERROR) {
+	    return TCL_ERROR;
+	}
+    }
+
+    /*
+     * Verify that it is indeed an array variable. This test comes after the
+     * traces - the variable may actually become an array as an effect of said
+     * traces. If not an array, it's an empty result.
+     */
+
+    if ((varPtr == NULL) || !TclIsVarArray(varPtr)
+	    || TclIsVarUndefined(varPtr)) {
+	return TCL_OK;
+    }
+
+    pattern = (patternObj ? TclGetString(patternObj) : NULL);
+
+    /*
+     * Store the array names in a new object.
+     */
+
+    TclNewObj(nameLstObj);
+    Tcl_IncrRefCount(nameLstObj);
+    if ((patternObj != NULL) && TclMatchIsTrivial(pattern)) {
+	varPtr2 = VarHashFindVar(varPtr->value.tablePtr, patternObj);
+	if (varPtr2 == NULL) {
+	    goto searchDone;
+	}
+	if (TclIsVarUndefined(varPtr2)) {
+	    goto searchDone;
+	}
+	result = Tcl_ListObjAppendElement(interp, nameLstObj,
+		VarHashGetKey(varPtr2));
+	if (result != TCL_OK) {
+	    TclDecrRefCount(nameLstObj);
+	    return result;
+	}
+	goto searchDone;
+    }
+
+    for (varPtr2 = VarHashFirstVar(varPtr->value.tablePtr, &search);
+	    varPtr2; varPtr2 = VarHashNextVar(&search)) {
+	if (TclIsVarUndefined(varPtr2)) {
+	    continue;
+	}
+	nameObj = VarHashGetKey(varPtr2);
+	if (patternObj && !Tcl_StringMatch(TclGetString(nameObj), pattern)) {
+	    continue;		/* Element name doesn't match pattern. */
+	}
+
+	result = Tcl_ListObjAppendElement(interp, nameLstObj, nameObj);
+	if (result != TCL_OK) {
+	    TclDecrRefCount(nameLstObj);
+	    return result;
+	}
+    }
+
+    /*
+     * Make sure the Var structure of the array is not removed by a trace
+     * while we're working.
+     */
+
+  searchDone:
+    if (TclIsVarInHash(varPtr)) {
+	VarHashRefCount(varPtr)++;
+    }
+
+    /*
+     * Get the array values corresponding to each element name.
+     */
+
+    TclNewObj(tmpResObj);
+    result = Tcl_ListObjGetElements(interp, nameLstObj, &count, &nameObjPtr);
+    if (result != TCL_OK) {
+	goto errorInArrayGet;
+    }
+
+    for (i=0 ; i<count ; i++) {
+	nameObj = *nameObjPtr++;
+	valueObj = Tcl_ObjGetVar2(interp, varNameObj, nameObj,
+		TCL_LEAVE_ERR_MSG);
+	if (valueObj == NULL) {
+	    /*
+	     * Some trace played a trick on us; we need to diagnose to adapt
+	     * our behaviour: was the array element unset, or did the
+	     * modification modify the complete array?
+	     */
+
+	    if (TclIsVarArray(varPtr)) {
+		/*
+		 * The array itself looks OK, the variable was undefined:
+		 * forget it.
+		 */
+
+		continue;
+	    }
+	    result = TCL_ERROR;
+	    goto errorInArrayGet;
+	}
+	result = Tcl_DictObjPut(interp, tmpResObj, nameObj, valueObj);
+	if (result != TCL_OK) {
+	    goto errorInArrayGet;
+	}
+    }
+    if (TclIsVarInHash(varPtr)) {
+	VarHashRefCount(varPtr)--;
+    }
+    Tcl_SetObjResult(interp, tmpResObj);
+    TclDecrRefCount(nameLstObj);
+    return TCL_OK;
+
+  errorInArrayGet:
+    if (TclIsVarInHash(varPtr)) {
+	VarHashRefCount(varPtr)--;
+    }
+    TclDecrRefCount(nameLstObj);
+    TclDecrRefCount(tmpResObj);	/* Free unneeded temp result. */
+    return result;
+}
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * ArrayNamesCmd --
+ *
+ *	This object-based function is invoked to process the "array names" Tcl
+ *	command. See the user documentation for details on what it does.
+ *
+ * Results:
+ *	A standard Tcl result object.
+ *
+ * Side effects:
+ *	See the user documentation.
+ *
+ *----------------------------------------------------------------------
+ */
+
+	/* ARGSUSED */
+static int
+ArrayNamesCmd(
+    ClientData clientData,
+    Tcl_Interp *interp,
+    int objc,
+    Tcl_Obj *const objv[])
+{
+    static const char *const options[] = {
+	"-exact", "-glob", "-regexp", NULL
+    };
+    enum options { OPT_EXACT, OPT_GLOB, OPT_REGEXP };
+    Interp *iPtr = (Interp *) interp;
+    Var *varPtr, *arrayPtr, *varPtr2;
+    Tcl_Obj *varNameObj, *nameObj, *resultObj, *patternObj;
+    Tcl_HashSearch search;
+    const char *pattern = NULL;
+    int mode = OPT_GLOB;
+
+    if ((objc < 2) || (objc > 4)) {
+	Tcl_WrongNumArgs(interp, 1, objv, "arrayName ?mode? ?pattern?");
+	return TCL_ERROR;
+    }
+    varNameObj = objv[1];
+    patternObj = (objc > 2 ? objv[objc-1] : NULL);
+
+    /*
+     * Locate the array variable.
+     */
+
+    varPtr = TclObjLookupVarEx(interp, varNameObj, NULL, /*flags*/ 0,
+	    /*msg*/ 0, /*createPart1*/ 0, /*createPart2*/ 0, &arrayPtr);
+
+    /*
+     * Special array trace used to keep the env array in sync for array names,
+     * array get, etc.
+     */
+
+    if (varPtr && (varPtr->flags & VAR_TRACED_ARRAY)
+	    && (TclIsVarArray(varPtr) || TclIsVarUndefined(varPtr))) {
+	if (TclObjCallVarTraces(iPtr, arrayPtr, varPtr, varNameObj, NULL,
+		(TCL_LEAVE_ERR_MSG|TCL_NAMESPACE_ONLY|TCL_GLOBAL_ONLY|
+		TCL_TRACE_ARRAY), /* leaveErrMsg */ 1, -1) == TCL_ERROR) {
+	    return TCL_ERROR;
+	}
+    }
+
+    /*
+     * Finish parsing the arguments.
+     */
+
+    if ((objc == 4) && Tcl_GetIndexFromObj(interp, objv[2], options, "option",
+	    0, &mode) != TCL_OK) {
+	return TCL_ERROR;
+    }
+
+    /*
+     * Verify that it is indeed an array variable. This test comes after the
+     * traces - the variable may actually become an array as an effect of said
+     * traces. If not an array, the result is empty.
+     */
+
+    if ((varPtr == NULL) || !TclIsVarArray(varPtr)
+	    || TclIsVarUndefined(varPtr)) {
+	return TCL_OK;
+    }
+
+    /*
+     * Check for the trivial cases where we can use a direct lookup.
+     */
+
+    TclNewObj(resultObj);
+    if (patternObj) {
+	pattern = TclGetString(patternObj);
+    }
+    if ((mode==OPT_GLOB && patternObj && TclMatchIsTrivial(pattern))
+	    || (mode==OPT_EXACT)) {
+	varPtr2 = VarHashFindVar(varPtr->value.tablePtr, patternObj);
+	if ((varPtr2 != NULL) && !TclIsVarUndefined(varPtr2)) {
+	    /*
+	     * This can't fail; lappending to an empty object always works.
+	     */
+
+	    Tcl_ListObjAppendElement(NULL, resultObj, VarHashGetKey(varPtr2));
+	}
+	Tcl_SetObjResult(interp, resultObj);
+	return TCL_OK;
+    }
+
+    /*
+     * Must scan the array to select the elements.
+     */
+
+    for (varPtr2=VarHashFirstVar(varPtr->value.tablePtr, &search);
+	    varPtr2!=NULL ; varPtr2=VarHashNextVar(&search)) {
+	if (TclIsVarUndefined(varPtr2)) {
+	    continue;
+	}
+	nameObj = VarHashGetKey(varPtr2);
+	if (patternObj) {
+	    const char *name = TclGetString(nameObj);
+	    int matched = 0;
+
+	    switch ((enum options) mode) {
+	    case OPT_EXACT:
+		Tcl_Panic("exact matching shouldn't get here");
+	    case OPT_GLOB:
+		matched = Tcl_StringMatch(name, pattern);
+		break;
+	    case OPT_REGEXP:
+		matched = Tcl_RegExpMatchObj(interp, nameObj, patternObj);
+		if (matched < 0) {
+		    TclDecrRefCount(resultObj);
+		    return TCL_ERROR;
+		}
+		break;
+	    }
+	    if (matched == 0) {
+		continue;
+	    }
+	}
+
+	Tcl_ListObjAppendElement(NULL, resultObj, nameObj);
+    }
+    Tcl_SetObjResult(interp, resultObj);
+    return TCL_OK;
+}
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * TclFindArrayPtrElements --
+ *
+ *	Fill out a hash table (which *must* use Tcl_Obj* keys) with an entry
+ *	for each existing element of the given array. The provided hash table
+ *	is assumed to be initially empty.
+ *
+ * Result:
+ *	none
+ *
+ * Side effects:
+ *	The keys of the array gain an extra reference. The supplied hash table
+ *	has elements added to it.
+ *
+ *----------------------------------------------------------------------
+ */
+
+void
+TclFindArrayPtrElements(
+    Var *arrayPtr,
+    Tcl_HashTable *tablePtr)
+{
+    Var *varPtr;
+    Tcl_HashSearch search;
+
+    if ((arrayPtr == NULL) || !TclIsVarArray(arrayPtr)
+	    || TclIsVarUndefined(arrayPtr)) {
+	return;
+    }
+
+    for (varPtr=VarHashFirstVar(arrayPtr->value.tablePtr, &search);
+	    varPtr!=NULL ; varPtr=VarHashNextVar(&search)) {
+	Tcl_HashEntry *hPtr;
+	Tcl_Obj *nameObj;
+	int dummy;
+
+	if (TclIsVarUndefined(varPtr)) {
+	    continue;
+	}
+	nameObj = VarHashGetKey(varPtr);
+	hPtr = Tcl_CreateHashEntry(tablePtr, (char *) nameObj, &dummy);
+	Tcl_SetHashValue(hPtr, nameObj);
+    }
+}
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * ArraySetCmd --
+ *
+ *	This object-based function is invoked to process the "array set" Tcl
+ *	command. See the user documentation for details on what it does.
+ *
+ * Results:
+ *	A standard Tcl result object.
+ *
+ * Side effects:
+ *	See the user documentation.
+ *
+ *----------------------------------------------------------------------
+ */
+
+	/* ARGSUSED */
+static int
+ArraySetCmd(
+    ClientData clientData,
+    Tcl_Interp *interp,
+    int objc,
+    Tcl_Obj *const objv[])
+{
+    Interp *iPtr = (Interp *) interp;
+    Var *varPtr, *arrayPtr;
+
+    if (objc != 3) {
+	Tcl_WrongNumArgs(interp, 1, objv, "arrayName list");
+	return TCL_ERROR;
+    }
+
+    /*
+     * Locate the array variable.
+     */
+
+    varPtr = TclObjLookupVarEx(interp, objv[1], NULL, /*flags*/ 0,
+	    /*msg*/ 0, /*createPart1*/ 0, /*createPart2*/ 0, &arrayPtr);
+
+    /*
+     * Special array trace used to keep the env array in sync for array names,
+     * array get, etc.
+     */
+
+    if (varPtr && (varPtr->flags & VAR_TRACED_ARRAY)
+	    && (TclIsVarArray(varPtr) || TclIsVarUndefined(varPtr))) {
+	if (TclObjCallVarTraces(iPtr, arrayPtr, varPtr, objv[1], NULL,
+		(TCL_LEAVE_ERR_MSG|TCL_NAMESPACE_ONLY|TCL_GLOBAL_ONLY|
+		TCL_TRACE_ARRAY), /* leaveErrMsg */ 1, -1) == TCL_ERROR) {
+	    return TCL_ERROR;
+	}
+    }
+
+    return TclArraySet(interp, objv[1], objv[2]);
+}
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * ArraySizeCmd --
+ *
+ *	This object-based function is invoked to process the "array size" Tcl
+ *	command. See the user documentation for details on what it does.
+ *
+ * Results:
+ *	A standard Tcl result object.
+ *
+ * Side effects:
+ *	See the user documentation.
+ *
+ *----------------------------------------------------------------------
+ */
+
+	/* ARGSUSED */
+static int
+ArraySizeCmd(
+    ClientData clientData,
+    Tcl_Interp *interp,
+    int objc,
+    Tcl_Obj *const objv[])
+{
+    Interp *iPtr = (Interp *) interp;
+    Var *varPtr, *arrayPtr;
+    Tcl_Obj *varNameObj;
+    Tcl_HashSearch search;
+    Var *varPtr2;
+    int size = 0;
+
+    if (objc != 2) {
+	Tcl_WrongNumArgs(interp, 1, objv, "arrayName");
+	return TCL_ERROR;
+    }
+    varNameObj = objv[1];
+
+    /*
+     * Locate the array variable.
+     */
+
+    varPtr = TclObjLookupVarEx(interp, varNameObj, NULL, /*flags*/ 0,
+	    /*msg*/ 0, /*createPart1*/ 0, /*createPart2*/ 0, &arrayPtr);
+
+    /*
+     * Special array trace used to keep the env array in sync for array names,
+     * array get, etc.
+     */
+
+    if (varPtr && (varPtr->flags & VAR_TRACED_ARRAY)
+	    && (TclIsVarArray(varPtr) || TclIsVarUndefined(varPtr))) {
+	if (TclObjCallVarTraces(iPtr, arrayPtr, varPtr, varNameObj, NULL,
+		(TCL_LEAVE_ERR_MSG|TCL_NAMESPACE_ONLY|TCL_GLOBAL_ONLY|
+		TCL_TRACE_ARRAY), /* leaveErrMsg */ 1, -1) == TCL_ERROR) {
+	    return TCL_ERROR;
+	}
+    }
+
+    /*
+     * Verify that it is indeed an array variable. This test comes after the
+     * traces - the variable may actually become an array as an effect of said
+     * traces. We can only iterate over the array if it exists...
+     */
+
+    if (varPtr && TclIsVarArray(varPtr) && !TclIsVarUndefined(varPtr)) {
+	/*
+	 * Must iterate in order to get chance to check for present but
+	 * "undefined" entries.
+	 */
+
+	for (varPtr2=VarHashFirstVar(varPtr->value.tablePtr, &search);
+		varPtr2!=NULL ; varPtr2=VarHashNextVar(&search)) {
+	    if (!TclIsVarUndefined(varPtr2)) {
+		size++;
+	    }
+	}
+    }
+
+    Tcl_SetObjResult(interp, Tcl_NewIntObj(size));
+    return TCL_OK;
+}
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * ArrayStatsCmd --
+ *
+ *	This object-based function is invoked to process the "array
+ *	statistics" Tcl command. See the user documentation for details on
+ *	what it does.
+ *
+ * Results:
+ *	A standard Tcl result object.
+ *
+ * Side effects:
+ *	See the user documentation.
+ *
+ *----------------------------------------------------------------------
+ */
+
+	/* ARGSUSED */
+static int
+ArrayStatsCmd(
+    ClientData clientData,
+    Tcl_Interp *interp,
+    int objc,
+    Tcl_Obj *const objv[])
+{
+    Interp *iPtr = (Interp *) interp;
+    Var *varPtr, *arrayPtr;
+    Tcl_Obj *varNameObj;
+    char *stats;
+
+    if (objc != 2) {
+	Tcl_WrongNumArgs(interp, 1, objv, "arrayName");
+	return TCL_ERROR;
+    }
+    varNameObj = objv[1];
+
+    /*
+     * Locate the array variable.
+     */
+
+    varPtr = TclObjLookupVarEx(interp, varNameObj, NULL, /*flags*/ 0,
+	    /*msg*/ 0, /*createPart1*/ 0, /*createPart2*/ 0, &arrayPtr);
+
+    /*
+     * Special array trace used to keep the env array in sync for array names,
+     * array get, etc.
+     */
+
+    if (varPtr && (varPtr->flags & VAR_TRACED_ARRAY)
+	    && (TclIsVarArray(varPtr) || TclIsVarUndefined(varPtr))) {
+	if (TclObjCallVarTraces(iPtr, arrayPtr, varPtr, varNameObj, NULL,
+		(TCL_LEAVE_ERR_MSG|TCL_NAMESPACE_ONLY|TCL_GLOBAL_ONLY|
+		TCL_TRACE_ARRAY), /* leaveErrMsg */ 1, -1) == TCL_ERROR) {
+	    return TCL_ERROR;
+	}
+    }
+
+    /*
+     * Verify that it is indeed an array variable. This test comes after the
+     * traces - the variable may actually become an array as an effect of said
+     * traces.
+     */
+
+    if ((varPtr == NULL) || !TclIsVarArray(varPtr)
+	    || TclIsVarUndefined(varPtr)) {
+	Tcl_SetObjResult(interp, Tcl_ObjPrintf(
+		"\"%s\" isn't an array", TclGetString(varNameObj)));
+	Tcl_SetErrorCode(interp, "TCL", "LOOKUP", "ARRAY",
+		TclGetString(varNameObj), NULL);
+	return TCL_ERROR;
+    }
+
+    stats = Tcl_HashStats((Tcl_HashTable *) varPtr->value.tablePtr);
+    if (stats == NULL) {
+	Tcl_SetObjResult(interp, Tcl_NewStringObj(
+		"error reading array statistics", -1));
+	return TCL_ERROR;
+    }
+    Tcl_SetObjResult(interp, Tcl_NewStringObj(stats, -1));
+    ckfree(stats);
+    return TCL_OK;
+}
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * ArrayUnsetCmd --
+ *
+ *	This object-based function is invoked to process the "array unset" Tcl
+ *	command. See the user documentation for details on what it does.
+ *
+ * Results:
+ *	A standard Tcl result object.
+ *
+ * Side effects:
+ *	See the user documentation.
+ *
+ *----------------------------------------------------------------------
+ */
+
+	/* ARGSUSED */
+static int
+ArrayUnsetCmd(
+    ClientData clientData,
+    Tcl_Interp *interp,
+    int objc,
+    Tcl_Obj *const objv[])
+{
+    Interp *iPtr = (Interp *) interp;
+    Var *varPtr, *arrayPtr, *varPtr2, *protectedVarPtr;
+    Tcl_Obj *varNameObj, *patternObj, *nameObj;
+    Tcl_HashSearch search;
+    const char *pattern;
+    const int unsetFlags = 0;	/* Should this be TCL_LEAVE_ERR_MSG? */
+
+    switch (objc) {
+    case 2:
+	varNameObj = objv[1];
+	patternObj = NULL;
+	break;
+    case 3:
+	varNameObj = objv[1];
+	patternObj = objv[2];
+	break;
+    default:
+	Tcl_WrongNumArgs(interp, 1, objv, "arrayName ?pattern?");
+	return TCL_ERROR;
+    }
+
+    /*
+     * Locate the array variable
+     */
+
+    varPtr = TclObjLookupVarEx(interp, varNameObj, NULL, /*flags*/ 0,
+	    /*msg*/ 0, /*createPart1*/ 0, /*createPart2*/ 0, &arrayPtr);
+
+    /*
+     * Special array trace used to keep the env array in sync for array names,
+     * array get, etc.
+     */
+
+    if (varPtr && (varPtr->flags & VAR_TRACED_ARRAY)
+	    && (TclIsVarArray(varPtr) || TclIsVarUndefined(varPtr))) {
+	if (TclObjCallVarTraces(iPtr, arrayPtr, varPtr, varNameObj, NULL,
+		(TCL_LEAVE_ERR_MSG|TCL_NAMESPACE_ONLY|TCL_GLOBAL_ONLY|
+		TCL_TRACE_ARRAY), /* leaveErrMsg */ 1, -1) == TCL_ERROR) {
+	    return TCL_ERROR;
+	}
+    }
+
+    /*
+     * Verify that it is indeed an array variable. This test comes after the
+     * traces - the variable may actually become an array as an effect of said
+     * traces.
+     */
+
+    if ((varPtr == NULL) || !TclIsVarArray(varPtr)
+	    || TclIsVarUndefined(varPtr)) {
+	return TCL_OK;
+    }
+
+    if (!patternObj) {
+	/*
+	 * When no pattern is given, just unset the whole array.
+	 */
+
+	return TclObjUnsetVar2(interp, varNameObj, NULL, 0);
+    }
+
+    /*
+     * With a trivial pattern, we can just unset.
+     */
+
+    pattern = TclGetString(patternObj);
+    if (TclMatchIsTrivial(pattern)) {
+	varPtr2 = VarHashFindVar(varPtr->value.tablePtr, patternObj);
+	if (!varPtr2 || TclIsVarUndefined(varPtr2)) {
+	    return TCL_OK;
+	}
+	return TclPtrUnsetVarIdx(interp, varPtr2, varPtr, varNameObj,
+		patternObj, unsetFlags, -1);
+    }
+
+    /*
+     * Non-trivial case (well, deeply tricky really). We peek inside the hash
+     * iterator in order to allow us to guarantee that the following element
+     * in the array will not be scrubbed until we have dealt with it. This
+     * stops the overall iterator from ending up pointing into deallocated
+     * memory. [Bug 2939073]
+     */
+
+    protectedVarPtr = NULL;
+    for (varPtr2=VarHashFirstVar(varPtr->value.tablePtr, &search);
+	    varPtr2!=NULL ; varPtr2=VarHashNextVar(&search)) {
+	/*
+	 * Drop the extra ref immediately. We don't need to free it at this
+	 * point though; we'll be unsetting it if necessary soon.
+	 */
+
+	if (varPtr2 == protectedVarPtr) {
+	    VarHashRefCount(varPtr2)--;
+	}
+
+	/*
+	 * Guard the next (peeked) item in the search chain by incrementing
+	 * its refcount. This guarantees that the hash table iterator won't be
+	 * dangling on the next time through the loop.
+	 */
+
+	if (search.nextEntryPtr != NULL) {
+	    protectedVarPtr = VarHashGetValue(search.nextEntryPtr);
+	    VarHashRefCount(protectedVarPtr)++;
+	} else {
+	    protectedVarPtr = NULL;
+	}
+
+	/*
+	 * If the variable is undefined, clean it out as it has been hit by
+	 * something else (i.e., an unset trace).
+	 */
+
+	if (TclIsVarUndefined(varPtr2)) {
+	    CleanupVar(varPtr2, varPtr);
+	    continue;
+	}
+
+	nameObj = VarHashGetKey(varPtr2);
+	if (Tcl_StringMatch(TclGetString(nameObj), pattern)
+		&& TclPtrUnsetVarIdx(interp, varPtr2, varPtr, varNameObj,
+			nameObj, unsetFlags, -1) != TCL_OK) {
+	    /*
+	     * If we incremented a refcount, we must decrement it here as we
+	     * will not be coming back properly due to the error.
+	     */
+
+	    if (protectedVarPtr) {
+		VarHashRefCount(protectedVarPtr)--;
+		CleanupVar(protectedVarPtr, varPtr);
+	    }
+	    return TCL_ERROR;
+	}
+    }
+    return TCL_OK;
+}
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * TclInitArrayCmd --
+ *
+ *	This creates the ensemble for the "array" command.
+ *
+ * Results:
+ *	The handle for the created ensemble.
+ *
+ * Side effects:
+ *	Creates a command in the global namespace.
+ *
+ *----------------------------------------------------------------------
+ */
+
+	/* ARGSUSED */
+Tcl_Command
+TclInitArrayCmd(
+    Tcl_Interp *interp)		/* Current interpreter. */
+{
+    static const EnsembleImplMap arrayImplMap[] = {
+	{"anymore",	ArrayAnyMoreCmd,	TclCompileBasic2ArgCmd, NULL, NULL, 0},
+	{"donesearch",	ArrayDoneSearchCmd,	TclCompileBasic2ArgCmd, NULL, NULL, 0},
+	{"exists",	ArrayExistsCmd,		TclCompileArrayExistsCmd, NULL, NULL, 0},
+	{"get",		ArrayGetCmd,		TclCompileBasic1Or2ArgCmd, NULL, NULL, 0},
+	{"names",	ArrayNamesCmd,		TclCompileBasic1To3ArgCmd, NULL, NULL, 0},
+	{"nextelement",	ArrayNextElementCmd,	TclCompileBasic2ArgCmd, NULL, NULL, 0},
+	{"set",		ArraySetCmd,		TclCompileArraySetCmd, NULL, NULL, 0},
+	{"size",	ArraySizeCmd,		TclCompileBasic1ArgCmd, NULL, NULL, 0},
+	{"startsearch",	ArrayStartSearchCmd,	TclCompileBasic1ArgCmd, NULL, NULL, 0},
+	{"statistics",	ArrayStatsCmd,		TclCompileBasic1ArgCmd, NULL, NULL, 0},
+	{"unset",	ArrayUnsetCmd,		TclCompileArrayUnsetCmd, NULL, NULL, 0},
+	{NULL, NULL, NULL, NULL, NULL, 0}
+    };
+
+    return TclMakeEnsemble(interp, "array", arrayImplMap);
+}
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * ObjMakeUpvar --
+ *
+ *	This function does all of the work of the "global" and "upvar"
+ *	commands.
+ *
+ * Results:
+ *	A standard Tcl completion code. If an error occurs then an error
+ *	message is left in iPtr->result.
+ *
+ * Side effects:
+ *	The variable given by myName is linked to the variable in framePtr
+ *	given by otherP1 and otherP2, so that references to myName are
+ *	redirected to the other variable like a symbolic link.
+ *	Callers must Incr myNamePtr if they plan to Decr it.
+ *	Callers must Incr otherP1Ptr if they plan to Decr it.
+ *
+ *----------------------------------------------------------------------
+ */
+
+static int
+ObjMakeUpvar(
+    Tcl_Interp *interp,		/* Interpreter containing variables. Used for
+				 * error messages, too. */
+    CallFrame *framePtr,	/* Call frame containing "other" variable.
+				 * NULL means use global :: context. */
+    Tcl_Obj *otherP1Ptr,
+    const char *otherP2,	/* Two-part name of variable in framePtr. */
+    const int otherFlags,	/* 0, TCL_GLOBAL_ONLY or TCL_NAMESPACE_ONLY:
+				 * indicates scope of "other" variable. */
+    Tcl_Obj *myNamePtr,		/* Name of variable which will refer to
+				 * otherP1/otherP2. Must be a scalar. */
+    int myFlags,		/* 0, TCL_GLOBAL_ONLY or TCL_NAMESPACE_ONLY:
+				 * indicates scope of myName. */
+    int index)			/* If the variable to be linked is an indexed
+				 * scalar, this is its index. Otherwise, -1 */
+{
+    Interp *iPtr = (Interp *) interp;
+    Var *otherPtr, *arrayPtr;
+    CallFrame *varFramePtr;
+
+    /*
+     * Find "other" in "framePtr". If not looking up other in just the current
+     * namespace, temporarily replace the current var frame pointer in the
+     * interpreter in order to use TclObjLookupVar.
+     */
+
+    if (framePtr == NULL) {
+	framePtr = iPtr->rootFramePtr;
+    }
+
+    varFramePtr = iPtr->varFramePtr;
+    if (!(otherFlags & TCL_NAMESPACE_ONLY)) {
+	iPtr->varFramePtr = framePtr;
+    }
+    otherPtr = TclObjLookupVar(interp, otherP1Ptr, otherP2,
+	    (otherFlags | TCL_LEAVE_ERR_MSG), "access",
+	    /*createPart1*/ 1, /*createPart2*/ 1, &arrayPtr);
+    if (!(otherFlags & TCL_NAMESPACE_ONLY)) {
+	iPtr->varFramePtr = varFramePtr;
+    }
+    if (otherPtr == NULL) {
+	return TCL_ERROR;
+    }
+
+    /*
+     * Check that we are not trying to create a namespace var linked to a
+     * local variable in a procedure. If we allowed this, the local
+     * variable in the shorter-lived procedure frame could go away leaving
+     * the namespace var's reference invalid.
+     */
+
+    if (index < 0) {
+	if (!(arrayPtr != NULL
+		     ? (TclIsVarInHash(arrayPtr) && TclGetVarNsPtr(arrayPtr))
+		     : (TclIsVarInHash(otherPtr) && TclGetVarNsPtr(otherPtr)))
+		&& ((myFlags & (TCL_GLOBAL_ONLY | TCL_NAMESPACE_ONLY))
+			|| (varFramePtr == NULL)
+			|| !HasLocalVars(varFramePtr)
+			|| (strstr(TclGetString(myNamePtr), "::") != NULL))) {
+	    Tcl_SetObjResult((Tcl_Interp *) iPtr, Tcl_ObjPrintf(
+		    "bad variable name \"%s\": can't create namespace "
+		    "variable that refers to procedure variable",
+		    TclGetString(myNamePtr)));
+	    Tcl_SetErrorCode(interp, "TCL", "UPVAR", "INVERTED", NULL);
+	    return TCL_ERROR;
+	}
+    }
+
+    return TclPtrObjMakeUpvarIdx(interp, otherPtr, myNamePtr, myFlags, index);
+}
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * TclPtrMakeUpvar --
+ *
+ *	This procedure does all of the work of the "global" and "upvar"
+ *	commands.
+ *
+ * Results:
+ *	A standard Tcl completion code. If an error occurs then an error
+ *	message is left in iPtr->result.
+ *
+ * Side effects:
+ *	The variable given by myName is linked to the variable in framePtr
+ *	given by otherP1 and otherP2, so that references to myName are
+ *	redirected to the other variable like a symbolic link.
+ *
+ *----------------------------------------------------------------------
+ */
+
+int
+TclPtrMakeUpvar(
+    Tcl_Interp *interp,		/* Interpreter containing variables. Used for
+				 * error messages, too. */
+    Var *otherPtr,		/* Pointer to the variable being linked-to. */
+    const char *myName,		/* Name of variable which will refer to
+				 * otherP1/otherP2. Must be a scalar. */
+    int myFlags,		/* 0, TCL_GLOBAL_ONLY or TCL_NAMESPACE_ONLY:
+				 * indicates scope of myName. */
+    int index)			/* If the variable to be linked is an indexed
+				 * scalar, this is its index. Otherwise, -1 */
+{
+    Tcl_Obj *myNamePtr = NULL;
+    int result;
+
+    if (myName) {
+	myNamePtr = Tcl_NewStringObj(myName, -1);
+	Tcl_IncrRefCount(myNamePtr);
+    }
+    result = TclPtrObjMakeUpvarIdx(interp, otherPtr, myNamePtr, myFlags,
+	    index);
+    if (myNamePtr) {
+	Tcl_DecrRefCount(myNamePtr);
+    }
+    return result;
+}
+
+int
+TclPtrObjMakeUpvar(
+    Tcl_Interp *interp,		/* Interpreter containing variables. Used for
+				 * error messages, too. */
+    Tcl_Var otherPtr,		/* Pointer to the variable being linked-to. */
+    Tcl_Obj *myNamePtr,		/* Name of variable which will refer to
+				 * otherP1/otherP2. Must be a scalar. */
+    int myFlags)		/* 0, TCL_GLOBAL_ONLY or TCL_NAMESPACE_ONLY:
+				 * indicates scope of myName. */
+{
+    return TclPtrObjMakeUpvarIdx(interp, (Var *) otherPtr, myNamePtr, myFlags,
+	    -1);
+}
+
+/* Callers must Incr myNamePtr if they plan to Decr it. */
+
+int
+TclPtrObjMakeUpvarIdx(
+    Tcl_Interp *interp,		/* Interpreter containing variables. Used for
+				 * error messages, too. */
+    Var *otherPtr,		/* Pointer to the variable being linked-to. */
+    Tcl_Obj *myNamePtr,		/* Name of variable which will refer to
+				 * otherP1/otherP2. Must be a scalar. */
+    int myFlags,		/* 0, TCL_GLOBAL_ONLY or TCL_NAMESPACE_ONLY:
+				 * indicates scope of myName. */
+    int index)			/* If the variable to be linked is an indexed
+				 * scalar, this is its index. Otherwise, -1 */
+{
+    Interp *iPtr = (Interp *) interp;
+    CallFrame *varFramePtr = iPtr->varFramePtr;
+    const char *errMsg, *p, *myName;
+    Var *varPtr;
+
+    if (index >= 0) {
+	if (!HasLocalVars(varFramePtr)) {
+	    Tcl_Panic("ObjMakeUpvar called with an index outside from a proc");
+	}
+	varPtr = (Var *) &(varFramePtr->compiledLocals[index]);
+	myNamePtr = localName(iPtr->varFramePtr, index);
+	myName = myNamePtr? TclGetString(myNamePtr) : NULL;
+    } else {
+	/*
+	 * Do not permit the new variable to look like an array reference, as
+	 * it will not be reachable in that case [Bug 600812, TIP 184]. The
+	 * "definition" of what "looks like an array reference" is consistent
+	 * (and must remain consistent) with the code in TclObjLookupVar().
+	 */
+
+	myName = TclGetString(myNamePtr);
+	p = strstr(myName, "(");
+	if (p != NULL) {
+	    p += strlen(p)-1;
+	    if (*p == ')') {
+		/*
+		 * myName looks like an array reference.
+		 */
+
+		Tcl_SetObjResult((Tcl_Interp *) iPtr, Tcl_ObjPrintf(
+			"bad variable name \"%s\": can't create a scalar "
+			"variable that looks like an array element", myName));
+		Tcl_SetErrorCode(interp, "TCL", "UPVAR", "LOCAL_ELEMENT",
+			NULL);
+		return TCL_ERROR;
+	    }
+	}
+
+	/*
+	 * Lookup and eventually create the new variable. Set the flag bit
+	 * TCL_AVOID_RESOLVERS to indicate the special resolution rules for
+	 * upvar purposes:
+	 *   - Bug #696893 - variable is either proc-local or in the current
+	 *     namespace; never follow the second (global) resolution path.
+	 *   - Bug #631741 - do not use special namespace or interp resolvers.
+	 */
+
+	varPtr = TclLookupSimpleVar(interp, myNamePtr,
+		myFlags|TCL_AVOID_RESOLVERS, /* create */ 1, &errMsg, &index);
+	if (varPtr == NULL) {
+	    TclObjVarErrMsg(interp, myNamePtr, NULL, "create", errMsg, -1);
+	    Tcl_SetErrorCode(interp, "TCL", "LOOKUP", "VARNAME",
+		    TclGetString(myNamePtr), NULL);
+	    return TCL_ERROR;
+	}
+    }
+
+    if (varPtr == otherPtr) {
+	Tcl_SetObjResult((Tcl_Interp *) iPtr, Tcl_NewStringObj(
+		"can't upvar from variable to itself", -1));
+	Tcl_SetErrorCode(interp, "TCL", "UPVAR", "SELF", NULL);
+	return TCL_ERROR;
+    }
+
+    if (TclIsVarTraced(varPtr)) {
+	Tcl_SetObjResult((Tcl_Interp *) iPtr, Tcl_ObjPrintf(
+		"variable \"%s\" has traces: can't use for upvar", myName));
+	Tcl_SetErrorCode(interp, "TCL", "UPVAR", "TRACED", NULL);
+	return TCL_ERROR;
+    } else if (!TclIsVarUndefined(varPtr)) {
+	Var *linkPtr;
+
+	/*
+	 * The variable already existed. Make sure this variable "varPtr"
+	 * isn't the same as "otherPtr" (avoid circular links). Also, if it's
+	 * not an upvar then it's an error. If it is an upvar, then just
+	 * disconnect it from the thing it currently refers to.
+	 */
+
+	if (!TclIsVarLink(varPtr)) {
+	    Tcl_SetObjResult((Tcl_Interp *) iPtr, Tcl_ObjPrintf(
+		    "variable \"%s\" already exists", myName));
+	    Tcl_SetErrorCode(interp, "TCL", "UPVAR", "EXISTS", NULL);
+	    return TCL_ERROR;
+	}
+
+	linkPtr = varPtr->value.linkPtr;
+	if (linkPtr == otherPtr) {
+	    return TCL_OK;
+	}
+	if (TclIsVarInHash(linkPtr)) {
+	    VarHashRefCount(linkPtr)--;
+	    if (TclIsVarUndefined(linkPtr)) {
+		CleanupVar(linkPtr, NULL);
+	    }
+	}
+    }
+    TclSetVarLink(varPtr);
+    varPtr->value.linkPtr = otherPtr;
+    if (TclIsVarInHash(otherPtr)) {
+	VarHashRefCount(otherPtr)++;
+    }
+    return TCL_OK;
+}
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * Tcl_UpVar --
+ *
+ *	This function links one variable to another, just like the "upvar"
+ *	command.
+ *
+ * Results:
+ *	A standard Tcl completion code. If an error occurs then an error
+ *	message is left in the interp's result.
+ *
+ * Side effects:
+ *	The variable in frameName whose name is given by varName becomes
+ *	accessible under the name localNameStr, so that references to
+ *	localNameStr are redirected to the other variable like a symbolic
+ *	link.
+ *
+ *----------------------------------------------------------------------
+ */
+
+#undef Tcl_UpVar
+int
+Tcl_UpVar(
+    Tcl_Interp *interp,		/* Command interpreter in which varName is to
+				 * be looked up. */
+    const char *frameName,	/* Name of the frame containing the source
+				 * variable, such as "1" or "#0". */
+    const char *varName,	/* Name of a variable in interp to link to.
+				 * May be either a scalar name or an element
+				 * in an array. */
+    const char *localNameStr,	/* Name of link variable. */
+    int flags)			/* 0, TCL_GLOBAL_ONLY or TCL_NAMESPACE_ONLY:
+				 * indicates scope of localNameStr. */
+{
+    int result;
+    CallFrame *framePtr;
+    Tcl_Obj *varNamePtr, *localNamePtr;
+
+    if (TclGetFrame(interp, frameName, &framePtr) == -1) {
+	return TCL_ERROR;
+    }
+
+    varNamePtr = Tcl_NewStringObj(varName, -1);
+    Tcl_IncrRefCount(varNamePtr);
+    localNamePtr = Tcl_NewStringObj(localNameStr, -1);
+    Tcl_IncrRefCount(localNamePtr);
+
+    result = ObjMakeUpvar(interp, framePtr, varNamePtr, NULL, 0,
+	    localNamePtr, flags, -1);
+    Tcl_DecrRefCount(varNamePtr);
+    Tcl_DecrRefCount(localNamePtr);
+    return result;
+}
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * Tcl_UpVar2 --
+ *
+ *	This function links one variable to another, just like the "upvar"
+ *	command.
+ *
+ * Results:
+ *	A standard Tcl completion code. If an error occurs then an error
+ *	message is left in the interp's result.
+ *
+ * Side effects:
+ *	The variable in frameName whose name is given by part1 and part2
+ *	becomes accessible under the name localNameStr, so that references to
+ *	localNameStr are redirected to the other variable like a symbolic
+ *	link.
+ *
+ *----------------------------------------------------------------------
+ */
+
+int
+Tcl_UpVar2(
+    Tcl_Interp *interp,		/* Interpreter containing variables. Used for
+				 * error messages too. */
+    const char *frameName,	/* Name of the frame containing the source
+				 * variable, such as "1" or "#0". */
+    const char *part1,
+    const char *part2,		/* Two parts of source variable name to link
+				 * to. */
+    const char *localNameStr,	/* Name of link variable. */
+    int flags)			/* 0, TCL_GLOBAL_ONLY or TCL_NAMESPACE_ONLY:
+				 * indicates scope of localNameStr. */
+{
+    int result;
+    CallFrame *framePtr;
+    Tcl_Obj *part1Ptr, *localNamePtr;
+
+    if (TclGetFrame(interp, frameName, &framePtr) == -1) {
+	return TCL_ERROR;
+    }
+
+    part1Ptr = Tcl_NewStringObj(part1, -1);
+    Tcl_IncrRefCount(part1Ptr);
+    localNamePtr = Tcl_NewStringObj(localNameStr, -1);
+    Tcl_IncrRefCount(localNamePtr);
+
+    result = ObjMakeUpvar(interp, framePtr, part1Ptr, part2, 0,
+	    localNamePtr, flags, -1);
+    Tcl_DecrRefCount(part1Ptr);
+    Tcl_DecrRefCount(localNamePtr);
+    return result;
+}
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * Tcl_GetVariableFullName --
+ *
+ *	Given a Tcl_Var token returned by Tcl_FindNamespaceVar, this function
+ *	appends to an object the namespace variable's full name, qualified by
+ *	a sequence of parent namespace names.
+ *
+ * Results:
+ *	None.
+ *
+ * Side effects:
+ *	The variable's fully-qualified name is appended to the string
+ *	representation of objPtr.
+ *
+ *----------------------------------------------------------------------
+ */
+
+void
+Tcl_GetVariableFullName(
+    Tcl_Interp *interp,		/* Interpreter containing the variable. */
+    Tcl_Var variable,		/* Token for the variable returned by a
+				 * previous call to Tcl_FindNamespaceVar. */
+    Tcl_Obj *objPtr)		/* Points to the object onto which the
+				 * variable's full name is appended. */
+{
+    Interp *iPtr = (Interp *) interp;
+    register Var *varPtr = (Var *) variable;
+    Tcl_Obj *namePtr;
+    Namespace *nsPtr;
+
+    if (!varPtr || TclIsVarArrayElement(varPtr)) {
+	return;
+    }
+
+    /*
+     * Add the full name of the containing namespace (if any), followed by the
+     * "::" separator, then the variable name.
+     */
+
+    nsPtr = TclGetVarNsPtr(varPtr);
+    if (nsPtr) {
+	Tcl_AppendToObj(objPtr, nsPtr->fullName, -1);
+	if (nsPtr != iPtr->globalNsPtr) {
+	    Tcl_AppendToObj(objPtr, "::", 2);
+	}
+    }
+    if (TclIsVarInHash(varPtr)) {
+	if (!TclIsVarDeadHash(varPtr)) {
+	    namePtr = VarHashGetKey(varPtr);
+	    Tcl_AppendObjToObj(objPtr, namePtr);
+	}
+    } else if (iPtr->varFramePtr->procPtr) {
+	int index = varPtr - iPtr->varFramePtr->compiledLocals;
+
+	if (index >= 0 && index < iPtr->varFramePtr->numCompiledLocals) {
+	    namePtr = localName(iPtr->varFramePtr, index);
+	    Tcl_AppendObjToObj(objPtr, namePtr);
+	}
+    }
+}
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * Tcl_GlobalObjCmd --
+ *
+ *	This object-based function is invoked to process the "global" Tcl
+ *	command. See the user documentation for details on what it does.
+ *
+ * Results:
+ *	A standard Tcl object result value.
+ *
+ * Side effects:
+ *	See the user documentation.
+ *
+ *----------------------------------------------------------------------
+ */
+
+int
+Tcl_GlobalObjCmd(
+    ClientData dummy,		/* Not used. */
+    Tcl_Interp *interp,		/* Current interpreter. */
+    int objc,			/* Number of arguments. */
+    Tcl_Obj *const objv[])	/* Argument objects. */
+{
+    Interp *iPtr = (Interp *) interp;
+    register Tcl_Obj *objPtr, *tailPtr;
+    const char *varName;
+    register const char *tail;
+    int result, i;
+
+    /*
+     * If we are not executing inside a Tcl procedure, just return.
+     */
+
+    if (!HasLocalVars(iPtr->varFramePtr)) {
+	return TCL_OK;
+    }
+
+    for (i=1 ; i<objc ; i++) {
+	/*
+	 * Make a local variable linked to its counterpart in the global ::
+	 * namespace.
+	 */
+
+	objPtr = objv[i];
+	varName = TclGetString(objPtr);
+
+	/*
+	 * The variable name might have a scope qualifier, but the name for
+	 * the local "link" variable must be the simple name at the tail.
+	 */
+
+	for (tail=varName ; *tail!='\0' ; tail++) {
+	    /* empty body */
+	}
+	while ((tail > varName) && ((*tail != ':') || (*(tail-1) != ':'))) {
+	    tail--;
+	}
+	if ((*tail == ':') && (tail > varName)) {
+	    tail++;
+	}
+
+	if (tail == varName) {
+	    tailPtr = objPtr;
+	} else {
+	    tailPtr = Tcl_NewStringObj(tail, -1);
+	    Tcl_IncrRefCount(tailPtr);
+	}
+
+	/*
+	 * Link to the variable "varName" in the global :: namespace.
+	 */
+
+	result = ObjMakeUpvar(interp, NULL, objPtr, NULL,
+		TCL_GLOBAL_ONLY, /*myName*/ tailPtr, /*myFlags*/ 0, -1);
+
+	if (tail != varName) {
+	    Tcl_DecrRefCount(tailPtr);
+	}
+
+	if (result != TCL_OK) {
+	    return result;
+	}
+    }
+    return TCL_OK;
+}
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * Tcl_VariableObjCmd --
+ *
+ *	Invoked to implement the "variable" command that creates one or more
+ *	global variables. Handles the following syntax:
+ *
+ *	    variable ?name value...? name ?value?
+ *
+ *	One or more variables can be created. The variables are initialized
+ *	with the specified values. The value for the last variable is
+ *	optional.
+ *
+ *	If the variable does not exist, it is created and given the optional
+ *	value. If it already exists, it is simply set to the optional value.
+ *	Normally, "name" is an unqualified name, so it is created in the
+ *	current namespace. If it includes namespace qualifiers, it can be
+ *	created in another namespace.
+ *
+ *	If the variable command is executed inside a Tcl procedure, it creates
+ *	a local variable linked to the newly-created namespace variable.
+ *
+ * Results:
+ *	Returns TCL_OK if the variable is found or created. Returns TCL_ERROR
+ *	if anything goes wrong.
+ *
+ * Side effects:
+ *	If anything goes wrong, this function returns an error message as the
+ *	result in the interpreter's result object.
+ *
+ *----------------------------------------------------------------------
+ */
+
+int
+Tcl_VariableObjCmd(
+    ClientData dummy,		/* Not used. */
+    Tcl_Interp *interp,		/* Current interpreter. */
+    int objc,			/* Number of arguments. */
+    Tcl_Obj *const objv[])	/* Argument objects. */
+{
+    Interp *iPtr = (Interp *) interp;
+    const char *varName, *tail, *cp;
+    Var *varPtr, *arrayPtr;
+    Tcl_Obj *varValuePtr;
+    int i, result;
+    Tcl_Obj *varNamePtr, *tailPtr;
+
+    for (i=1 ; i<objc ; i+=2) {
+	/*
+	 * Look up each variable in the current namespace context, creating it
+	 * if necessary.
+	 */
+
+	varNamePtr = objv[i];
+	varName = TclGetString(varNamePtr);
+	varPtr = TclObjLookupVarEx(interp, varNamePtr, NULL,
+		(TCL_NAMESPACE_ONLY | TCL_LEAVE_ERR_MSG), "define",
+		/*createPart1*/ 1, /*createPart2*/ 0, &arrayPtr);
+
+	if (arrayPtr != NULL) {
+	    /*
+	     * Variable cannot be an element in an array. If arrayPtr is
+	     * non-NULL, it is, so throw up an error and return.
+	     */
+
+	    TclObjVarErrMsg(interp, varNamePtr, NULL, "define",
+		    isArrayElement, -1);
+	    Tcl_SetErrorCode(interp, "TCL", "UPVAR", "LOCAL_ELEMENT", NULL);
+	    return TCL_ERROR;
+	}
+
+	if (varPtr == NULL) {
+	    return TCL_ERROR;
+	}
+
+	/*
+	 * Mark the variable as a namespace variable and increment its
+	 * reference count so that it will persist until its namespace is
+	 * destroyed or until the variable is unset.
+	 */
+
+	TclSetVarNamespaceVar(varPtr);
+
+	/*
+	 * If a value was specified, set the variable to that value.
+	 * Otherwise, if the variable is new, leave it undefined. (If the
+	 * variable already exists and no value was specified, leave its value
+	 * unchanged; just create the local link if we're in a Tcl procedure).
+	 */
+
+	if (i+1 < objc) {	/* A value was specified. */
+	    varValuePtr = TclPtrSetVarIdx(interp, varPtr, arrayPtr,
+		    varNamePtr, NULL, objv[i+1],
+		    (TCL_NAMESPACE_ONLY | TCL_LEAVE_ERR_MSG), -1);
+	    if (varValuePtr == NULL) {
+		return TCL_ERROR;
+	    }
+	}
+
+	/*
+	 * If we are executing inside a Tcl procedure, create a local variable
+	 * linked to the new namespace variable "varName".
+	 */
+
+	if (HasLocalVars(iPtr->varFramePtr)) {
+	    /*
+	     * varName might have a scope qualifier, but the name for the
+	     * local "link" variable must be the simple name at the tail.
+	     *
+	     * Locate tail in one pass: drop any prefix after two *or more*
+	     * consecutive ":" characters).
+	     */
+
+	    for (tail=cp=varName ; *cp!='\0' ;) {
+		if (*cp++ == ':') {
+		    while (*cp == ':') {
+			tail = ++cp;
+		    }
+		}
+	    }
+
+	    /*
+	     * Create a local link "tail" to the variable "varName" in the
+	     * current namespace.
+	     */
+
+	    if (tail == varName) {
+		tailPtr = varNamePtr;
+	    } else {
+		tailPtr = Tcl_NewStringObj(tail, -1);
+		Tcl_IncrRefCount(tailPtr);
+	    }
+
+	    result = ObjMakeUpvar(interp, NULL, varNamePtr, /*otherP2*/ NULL,
+		    /*otherFlags*/ TCL_NAMESPACE_ONLY,
+		    /*myName*/ tailPtr, /*myFlags*/ 0, -1);
+
+	    if (tail != varName) {
+		Tcl_DecrRefCount(tailPtr);
+	    }
+
+	    if (result != TCL_OK) {
+		return result;
+	    }
+	}
+    }
+    return TCL_OK;
+}
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * Tcl_UpvarObjCmd --
+ *
+ *	This object-based function is invoked to process the "upvar" Tcl
+ *	command. See the user documentation for details on what it does.
+ *
+ * Results:
+ *	A standard Tcl object result value.
+ *
+ * Side effects:
+ *	See the user documentation.
+ *
+ *----------------------------------------------------------------------
+ */
+
+	/* ARGSUSED */
+int
+Tcl_UpvarObjCmd(
+    ClientData dummy,		/* Not used. */
+    Tcl_Interp *interp,		/* Current interpreter. */
+    int objc,			/* Number of arguments. */
+    Tcl_Obj *const objv[])	/* Argument objects. */
+{
+    CallFrame *framePtr;
+    int result, hasLevel;
+    Tcl_Obj *levelObj;
+
+    if (objc < 3) {
+	Tcl_WrongNumArgs(interp, 1, objv,
+		"?level? otherVar localVar ?otherVar localVar ...?");
+	return TCL_ERROR;
+    }
+
+    if (objc & 1) {
+	/*
+	 * Even number of arguments, so use the default level of "1" by
+	 * passing NULL to TclObjGetFrame.
+	 */
+
+	levelObj = NULL;
+	hasLevel = 0;
+    } else {
+	/*
+	 * Odd number of arguments, so objv[1] must contain the level.
+	 */
+
+	levelObj = objv[1];
+	hasLevel = 1;
+    }
+
+    /*
+     * Find the call frame containing each of the "other variables" to be
+     * linked to.
+     */
+
+    result = TclObjGetFrame(interp, levelObj, &framePtr);
+    if (result == -1) {
+	return TCL_ERROR;
+    }
+    if ((result == 0) && hasLevel) {
+	/*
+	 * Synthesize an error message since TclObjGetFrame doesn't do this
+	 * for this particular case.
+	 */
+
+	Tcl_SetObjResult(interp, Tcl_ObjPrintf(
+		"bad level \"%s\"", TclGetString(levelObj)));
+	Tcl_SetErrorCode(interp, "TCL", "LOOKUP", "LEVEL",
+		TclGetString(levelObj), NULL);
+	return TCL_ERROR;
+    }
+
+    /*
+     * We've now finished with parsing levels; skip to the variable names.
+     */
+
+    objc -= hasLevel + 1;
+    objv += hasLevel + 1;
+
+    /*
+     * Iterate over each (other variable, local variable) pair. Divide the
+     * other variable name into two parts, then call MakeUpvar to do all the
+     * work of linking it to the local variable.
+     */
+
+    for (; objc>0 ; objc-=2, objv+=2) {
+	result = ObjMakeUpvar(interp, framePtr, /* othervarName */ objv[0],
+		NULL, 0, /* myVarName */ objv[1], /*flags*/ 0, -1);
+	if (result != TCL_OK) {
+	    return TCL_ERROR;
+	}
+    }
+    return TCL_OK;
+}
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * SetArraySearchObj --
+ *
+ *	This function converts the given tcl object into one that has the
+ *	"array search" internal type.
+ *
+ * Results:
+ *	TCL_OK if the conversion succeeded, and TCL_ERROR if it failed (when
+ *	an error message will be placed in the interpreter's result.)
+ *
+ * Side effects:
+ *	Updates the internal type and representation of the object to make
+ *	this an array-search object. See the tclArraySearchType declaration
+ *	above for details of the internal representation.
+ *
+ *----------------------------------------------------------------------
+ */
+
+static int
+SetArraySearchObj(
+    Tcl_Interp *interp,
+    Tcl_Obj *objPtr)
+{
+    const char *string;
+    char *end;			/* Can't be const due to strtoul defn. */
+    int id;
+    size_t offset;
+
+    /*
+     * Get the string representation. Make it up-to-date if necessary.
+     */
+
+    string = TclGetString(objPtr);
+
+    /*
+     * Parse the id into the three parts separated by dashes.
+     */
+
+    if ((string[0] != 's') || (string[1] != '-')) {
+	goto syntax;
+    }
+    id = strtoul(string+2, &end, 10);
+    if ((end == (string+2)) || (*end != '-')) {
+	goto syntax;
+    }
+
+    /*
+     * Can't perform value check in this context, so place reference to place
+     * in string to use for the check in the object instead.
+     */
+
+    end++;
+    offset = end - string;
+
+    TclFreeIntRep(objPtr);
+    objPtr->typePtr = &tclArraySearchType;
+    objPtr->internalRep.twoPtrValue.ptr1 = INT2PTR(id);
+    objPtr->internalRep.twoPtrValue.ptr2 = INT2PTR(offset);
+    return TCL_OK;
+
+  syntax:
+    Tcl_SetObjResult(interp, Tcl_ObjPrintf(
+	    "illegal search identifier \"%s\"", string));
+    Tcl_SetErrorCode(interp, "TCL", "LOOKUP", "ARRAYSEARCH", string, NULL);
+    return TCL_ERROR;
+}
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * ParseSearchId --
+ *
+ *	This function translates from a tcl object to a pointer to an active
+ *	array search (if there is one that matches the string).
+ *
+ * Results:
+ *	The return value is a pointer to the array search indicated by string,
+ *	or NULL if there isn't one. If NULL is returned, the interp's result
+ *	contains an error message.
+ *
+ * Side effects:
+ *	The tcl object might have its internal type and representation
+ *	modified.
+ *
+ *----------------------------------------------------------------------
+ */
+
+static ArraySearch *
+ParseSearchId(
+    Tcl_Interp *interp,		/* Interpreter containing variable. */
+    const Var *varPtr,		/* Array variable search is for. */
+    Tcl_Obj *varNamePtr,	/* Name of array variable that search is
+				 * supposed to be for. */
+    Tcl_Obj *handleObj)		/* Object containing id of search. Must have
+				 * form "search-num-var" where "num" is a
+				 * decimal number and "var" is a variable
+				 * name. */
+{
+    Interp *iPtr = (Interp *) interp;
+    register const char *string;
+    register size_t offset;
+    int id;
+    ArraySearch *searchPtr;
+    const char *varName = TclGetString(varNamePtr);
+
+    /*
+     * Parse the id.
+     */
+
+    if ((handleObj->typePtr != &tclArraySearchType)
+	    && (SetArraySearchObj(interp, handleObj) != TCL_OK)) {
+	return NULL;
+    }
+
+    /*
+     * Extract the information out of the Tcl_Obj.
+     */
+
+    id = PTR2INT(handleObj->internalRep.twoPtrValue.ptr1);
+    string = TclGetString(handleObj);
+    offset = PTR2INT(handleObj->internalRep.twoPtrValue.ptr2);
+
+    /*
+     * This test cannot be placed inside the Tcl_Obj machinery, since it is
+     * dependent on the variable context.
+     */
+
+    if (strcmp(string+offset, varName) != 0) {
+	Tcl_SetObjResult(interp, Tcl_ObjPrintf(
+		"search identifier \"%s\" isn't for variable \"%s\"",
+		string, varName));
+	goto badLookup;
+    }
+
+    /*
+     * Search through the list of active searches on the interpreter to see if
+     * the desired one exists.
+     *
+     * Note that we cannot store the searchPtr directly in the Tcl_Obj as that
+     * would run into trouble when DeleteSearches() was called so we must scan
+     * this list every time.
+     */
+
+    if (varPtr->flags & VAR_SEARCH_ACTIVE) {
+	Tcl_HashEntry *hPtr =
+		Tcl_FindHashEntry(&iPtr->varSearches, varPtr);
+
+	for (searchPtr = Tcl_GetHashValue(hPtr); searchPtr != NULL;
+		searchPtr = searchPtr->nextPtr) {
+	    if (searchPtr->id == id) {
+		return searchPtr;
+	    }
+	}
+    }
+    Tcl_SetObjResult(interp, Tcl_ObjPrintf(
+	    "couldn't find search \"%s\"", string));
+  badLookup:
+    Tcl_SetErrorCode(interp, "TCL", "LOOKUP", "ARRAYSEARCH", string, NULL);
+    return NULL;
+}
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * DeleteSearches --
+ *
+ *	This function is called to free up all of the searches associated
+ *	with an array variable.
+ *
+ * Results:
+ *	None.
+ *
+ * Side effects:
+ *	Memory is released to the storage allocator.
+ *
+ *----------------------------------------------------------------------
+ */
+
+static void
+DeleteSearches(
+    Interp *iPtr,
+    register Var *arrayVarPtr)	/* Variable whose searches are to be
+				 * deleted. */
+{
+    ArraySearch *searchPtr, *nextPtr;
+    Tcl_HashEntry *sPtr;
+
+    if (arrayVarPtr->flags & VAR_SEARCH_ACTIVE) {
+	sPtr = Tcl_FindHashEntry(&iPtr->varSearches, arrayVarPtr);
+	for (searchPtr = Tcl_GetHashValue(sPtr); searchPtr != NULL;
+		searchPtr = nextPtr) {
+	    nextPtr = searchPtr->nextPtr;
+	    ckfree(searchPtr);
+	}
+	arrayVarPtr->flags &= ~VAR_SEARCH_ACTIVE;
+	Tcl_DeleteHashEntry(sPtr);
+    }
+}
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * TclDeleteNamespaceVars --
+ *
+ *	This function is called to recycle all the storage space associated
+ *	with a namespace's table of variables.
+ *
+ * Results:
+ *	None.
+ *
+ * Side effects:
+ *	Variables are deleted and trace functions are invoked, if any are
+ *	declared.
+ *
+ *----------------------------------------------------------------------
+ */
+
+void
+TclDeleteNamespaceVars(
+    Namespace *nsPtr)
+{
+    TclVarHashTable *tablePtr = &nsPtr->varTable;
+    Tcl_Interp *interp = nsPtr->interp;
+    Interp *iPtr = (Interp *)interp;
+    Tcl_HashSearch search;
+    int flags = 0;
+    Var *varPtr;
+
+    /*
+     * Determine what flags to pass to the trace callback functions.
+     */
+
+    if (nsPtr == iPtr->globalNsPtr) {
+	flags = TCL_GLOBAL_ONLY;
+    } else if (nsPtr == (Namespace *) TclGetCurrentNamespace(interp)) {
+	flags = TCL_NAMESPACE_ONLY;
+    }
+
+    for (varPtr = VarHashFirstVar(tablePtr, &search);  varPtr != NULL;
+	    varPtr = VarHashFirstVar(tablePtr, &search)) {
+	Tcl_Obj *objPtr = Tcl_NewObj();
+	VarHashRefCount(varPtr)++;	/* Make sure we get to remove from
+					 * hash. */
+	Tcl_GetVariableFullName(interp, (Tcl_Var) varPtr, objPtr);
+	UnsetVarStruct(varPtr, NULL, iPtr, /* part1 */ objPtr,
+		NULL, flags, -1);
+
+	/*
+	 * We just unset the variable. However, an unset trace might
+	 * have re-set it, or might have re-established traces on it.
+	 * This namespace and its vartable are going away unconditionally,
+	 * so we cannot let such things linger. That would be a leak.
+	 *
+	 * First we destroy all traces. ...
+	 */
+
+	if (TclIsVarTraced(varPtr)) {
+	    Tcl_HashEntry *tPtr = Tcl_FindHashEntry(&iPtr->varTraces, varPtr);
+	    VarTrace *tracePtr = Tcl_GetHashValue(tPtr);
+	    ActiveVarTrace *activePtr;
+
+	    while (tracePtr) {
+		VarTrace *prevPtr = tracePtr;
+
+		tracePtr = tracePtr->nextPtr;
+		prevPtr->nextPtr = NULL;
+		Tcl_EventuallyFree(prevPtr, TCL_DYNAMIC);
+	    }
+	    Tcl_DeleteHashEntry(tPtr);
+	    varPtr->flags &= ~VAR_ALL_TRACES;
+	    for (activePtr = iPtr->activeVarTracePtr; activePtr != NULL;
+		    activePtr = activePtr->nextPtr) {
+		if (activePtr->varPtr == varPtr) {
+		    activePtr->nextTracePtr = NULL;
+		}
+	    }
+	}
+
+	/*
+	 * ...and then, if the variable still holds a value, we unset it
+	 * again. This time with no traces left, we're sure it goes away.
+	 */
+
+	if (!TclIsVarUndefined(varPtr)) {
+	    UnsetVarStruct(varPtr, NULL, iPtr, /* part1 */ objPtr,
+		    NULL, flags, -1);
+	}
+	Tcl_DecrRefCount(objPtr); /* free no longer needed obj */
+	VarHashRefCount(varPtr)--;
+	VarHashDeleteEntry(varPtr);
+    }
+    VarHashDeleteTable(tablePtr);
+}
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * TclDeleteVars --
+ *
+ *	This function is called to recycle all the storage space associated
+ *	with a table of variables. For this function to work correctly, it
+ *	must not be possible for any of the variables in the table to be
+ *	accessed from Tcl commands (e.g. from trace functions).
+ *
+ * Results:
+ *	None.
+ *
+ * Side effects:
+ *	Variables are deleted and trace functions are invoked, if any are
+ *	declared.
+ *
+ *----------------------------------------------------------------------
+ */
+
+void
+TclDeleteVars(
+    Interp *iPtr,		/* Interpreter to which variables belong. */
+    TclVarHashTable *tablePtr)	/* Hash table containing variables to
+				 * delete. */
+{
+    Tcl_Interp *interp = (Tcl_Interp *) iPtr;
+    Tcl_HashSearch search;
+    register Var *varPtr;
+    int flags;
+    Namespace *currNsPtr = (Namespace *) TclGetCurrentNamespace(interp);
+
+    /*
+     * Determine what flags to pass to the trace callback functions.
+     */
+
+    flags = TCL_TRACE_UNSETS;
+    if (tablePtr == &iPtr->globalNsPtr->varTable) {
+	flags |= TCL_GLOBAL_ONLY;
+    } else if (tablePtr == &currNsPtr->varTable) {
+	flags |= TCL_NAMESPACE_ONLY;
+    }
+
+    for (varPtr = VarHashFirstVar(tablePtr, &search); varPtr != NULL;
+	 varPtr = VarHashFirstVar(tablePtr, &search)) {
+	UnsetVarStruct(varPtr, NULL, iPtr, VarHashGetKey(varPtr), NULL, flags,
+		-1);
+	VarHashDeleteEntry(varPtr);
+    }
+    VarHashDeleteTable(tablePtr);
+}
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * TclDeleteCompiledLocalVars --
+ *
+ *	This function is called to recycle storage space associated with the
+ *	compiler-allocated array of local variables in a procedure call frame.
+ *	This function resembles TclDeleteVars above except that each variable
+ *	is stored in a call frame and not a hash table. For this function to
+ *	work correctly, it must not be possible for any of the variable in the
+ *	table to be accessed from Tcl commands (e.g. from trace functions).
+ *
+ * Results:
+ *	None.
+ *
+ * Side effects:
+ *	Variables are deleted and trace functions are invoked, if any are
+ *	declared.
+ *
+ *----------------------------------------------------------------------
+ */
+
+void
+TclDeleteCompiledLocalVars(
+    Interp *iPtr,		/* Interpreter to which variables belong. */
+    CallFrame *framePtr)	/* Procedure call frame containing compiler-
+				 * assigned local variables to delete. */
+{
+    register Var *varPtr;
+    int numLocals, i;
+    Tcl_Obj **namePtrPtr;
+
+    numLocals = framePtr->numCompiledLocals;
+    varPtr = framePtr->compiledLocals;
+    namePtrPtr = &localName(framePtr, 0);
+    for (i=0 ; i<numLocals ; i++, namePtrPtr++, varPtr++) {
+	UnsetVarStruct(varPtr, NULL, iPtr, *namePtrPtr, NULL,
+		TCL_TRACE_UNSETS, i);
+    }
+    framePtr->numCompiledLocals = 0;
+}
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * DeleteArray --
+ *
+ *	This function is called to free up everything in an array variable.
+ *	It's the caller's responsibility to make sure that the array is no
+ *	longer accessible before this function is called.
+ *
+ * Results:
+ *	None.
+ *
+ * Side effects:
+ *	All storage associated with varPtr's array elements is deleted
+ *	(including the array's hash table). Deletion trace functions for
+ *	array elements are invoked, then deleted. Any pending traces for array
+ *	elements are also deleted.
+ *
+ *----------------------------------------------------------------------
+ */
+
+static void
+DeleteArray(
+    Interp *iPtr,		/* Interpreter containing array. */
+    Tcl_Obj *arrayNamePtr,	/* Name of array (used for trace callbacks),
+				 * or NULL if it is to be computed on
+				 * demand. */
+    Var *varPtr,		/* Pointer to variable structure. */
+    int flags,			/* Flags to pass to TclCallVarTraces:
+				 * TCL_TRACE_UNSETS and sometimes
+				 * TCL_NAMESPACE_ONLY or TCL_GLOBAL_ONLY. */
+    int index)
+{
+    Tcl_HashSearch search;
+    Tcl_HashEntry *tPtr;
+    register Var *elPtr;
+    ActiveVarTrace *activePtr;
+    Tcl_Obj *objPtr;
+    VarTrace *tracePtr;
+
+    if (varPtr->flags & VAR_SEARCH_ACTIVE) {
+	DeleteSearches(iPtr, varPtr);
+    }
+    for (elPtr = VarHashFirstVar(varPtr->value.tablePtr, &search);
+	    elPtr != NULL; elPtr = VarHashNextVar(&search)) {
+	if (TclIsVarScalar(elPtr) && (elPtr->value.objPtr != NULL)) {
+	    objPtr = elPtr->value.objPtr;
+	    TclDecrRefCount(objPtr);
+	    elPtr->value.objPtr = NULL;
+	}
+
+	/*
+	 * Lie about the validity of the hashtable entry. In this way the
+	 * variables will be deleted by VarHashDeleteTable.
+	 */
+
+	VarHashInvalidateEntry(elPtr);
+	if (TclIsVarTraced(elPtr)) {
+	    /*
+	     * Compute the array name if it was not supplied.
+	     */
+
+	    if (elPtr->flags & VAR_TRACED_UNSET) {
+		Tcl_Obj *elNamePtr = VarHashGetKey(elPtr);
+
+		elPtr->flags &= ~VAR_TRACE_ACTIVE;
+		TclObjCallVarTraces(iPtr, NULL, elPtr, arrayNamePtr,
+			elNamePtr, flags,/* leaveErrMsg */ 0, index);
+	    }
+	    tPtr = Tcl_FindHashEntry(&iPtr->varTraces, elPtr);
+	    tracePtr = Tcl_GetHashValue(tPtr);
+	    while (tracePtr) {
+		VarTrace *prevPtr = tracePtr;
+
+		tracePtr = tracePtr->nextPtr;
+		prevPtr->nextPtr = NULL;
+		Tcl_EventuallyFree(prevPtr, TCL_DYNAMIC);
+	    }
+	    Tcl_DeleteHashEntry(tPtr);
+	    elPtr->flags &= ~VAR_ALL_TRACES;
+	    for (activePtr = iPtr->activeVarTracePtr; activePtr != NULL;
+		    activePtr = activePtr->nextPtr) {
+		if (activePtr->varPtr == elPtr) {
+		    activePtr->nextTracePtr = NULL;
+		}
+	    }
+	}
+	TclSetVarUndefined(elPtr);
+
+	/*
+	 * Even though array elements are not supposed to be namespace
+	 * variables, some combinations of [upvar] and [variable] may create
+	 * such beasts - see [Bug 604239]. This is necessary to avoid leaking
+	 * the corresponding Var struct, and is otherwise harmless.
+	 */
+
+	TclClearVarNamespaceVar(elPtr);
+    }
+    VarHashDeleteTable(varPtr->value.tablePtr);
+    ckfree(varPtr->value.tablePtr);
+}
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * TclObjVarErrMsg --
+ *
+ *	Generate a reasonable error message describing why a variable
+ *	operation failed.
+ *
+ * Results:
+ *	None.
+ *
+ * Side effects:
+ *	The interp's result is set to hold a message identifying the variable
+ *	given by part1 and part2 and describing why the variable operation
+ *	failed.
+ *
+ *----------------------------------------------------------------------
+ */
+
+void
+TclVarErrMsg(
+    Tcl_Interp *interp,		/* Interpreter in which to record message. */
+    const char *part1,
+    const char *part2,		/* Variable's two-part name. */
+    const char *operation,	/* String describing operation that failed,
+				 * e.g. "read", "set", or "unset". */
+    const char *reason)		/* String describing why operation failed. */
+{
+    Tcl_Obj *part2Ptr = NULL, *part1Ptr = Tcl_NewStringObj(part1, -1);
+
+    if (part2) {
+	part2Ptr = Tcl_NewStringObj(part2, -1);
+    }
+
+    TclObjVarErrMsg(interp, part1Ptr, part2Ptr, operation, reason, -1);
+
+    Tcl_DecrRefCount(part1Ptr);
+    if (part2Ptr) {
+	Tcl_DecrRefCount(part2Ptr);
+    }
+}
+
+void
+TclObjVarErrMsg(
+    Tcl_Interp *interp,		/* Interpreter in which to record message. */
+    Tcl_Obj *part1Ptr,		/* (may be NULL, if index >= 0) */
+    Tcl_Obj *part2Ptr,		/* Variable's two-part name. */
+    const char *operation,	/* String describing operation that failed,
+				 * e.g. "read", "set", or "unset". */
+    const char *reason,		/* String describing why operation failed. */
+    int index)			/* Index into the local variable table of the
+				 * variable, or -1. Only used when part1Ptr is
+				 * NULL. */
+{
+    if (!part1Ptr) {
+	if (index == -1) {
+	    Tcl_Panic("invalid part1Ptr and invalid index together");
+	}
+	part1Ptr = localName(((Interp *)interp)->varFramePtr, index);
+    }
+    Tcl_SetObjResult(interp, Tcl_ObjPrintf("can't %s \"%s%s%s%s\": %s",
+	    operation, TclGetString(part1Ptr), (part2Ptr ? "(" : ""),
+	    (part2Ptr ? TclGetString(part2Ptr) : ""), (part2Ptr ? ")" : ""),
+	    reason));
+}
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * Internal functions for variable name object types --
+ *
+ *----------------------------------------------------------------------
+ */
+
+/*
+ * Panic functions that should never be called in normal operation.
+ */
+
+static void
+PanicOnUpdateVarName(
+    Tcl_Obj *objPtr)
+{
+    Tcl_Panic("%s of type %s should not be called", "updateStringProc",
+	    objPtr->typePtr->name);
+}
+
+static int
+PanicOnSetVarName(
+    Tcl_Interp *interp,
+    Tcl_Obj *objPtr)
+{
+    Tcl_Panic("%s of type %s should not be called", "setFromAnyProc",
+	    objPtr->typePtr->name);
+    return TCL_ERROR;
+}
+
+/*
+ * localVarName -
+ *
+ * INTERNALREP DEFINITION:
+ *   twoPtrValue.ptr1:   pointer to name obj in varFramePtr->localCache
+ *			  or NULL if it is this same obj
+ *   twoPtrValue.ptr2: index into locals table
+ */
+
+static void
+FreeLocalVarName(
+    Tcl_Obj *objPtr)
+{
+    Tcl_Obj *namePtr = objPtr->internalRep.twoPtrValue.ptr1;
+
+    if (namePtr) {
+	Tcl_DecrRefCount(namePtr);
+    }
+    objPtr->typePtr = NULL;
+}
+
+static void
+DupLocalVarName(
+    Tcl_Obj *srcPtr,
+    Tcl_Obj *dupPtr)
+{
+    Tcl_Obj *namePtr = srcPtr->internalRep.twoPtrValue.ptr1;
+
+    if (!namePtr) {
+	namePtr = srcPtr;
+    }
+    dupPtr->internalRep.twoPtrValue.ptr1 = namePtr;
+    Tcl_IncrRefCount(namePtr);
+
+    dupPtr->internalRep.twoPtrValue.ptr2 =
+	    srcPtr->internalRep.twoPtrValue.ptr2;
+    dupPtr->typePtr = &localVarNameType;
+}
+
+/*
+ * parsedVarName -
+ *
+ * INTERNALREP DEFINITION:
+ *   twoPtrValue.ptr1 = pointer to the array name Tcl_Obj (NULL if scalar)
+ *   twoPtrValue.ptr2 = pointer to the element name string (owned by this
+ *			Tcl_Obj), or NULL if it is a scalar variable
+ */
+
+static void
+FreeParsedVarName(
+    Tcl_Obj *objPtr)
+{
+    register Tcl_Obj *arrayPtr = objPtr->internalRep.twoPtrValue.ptr1;
+    register char *elem = objPtr->internalRep.twoPtrValue.ptr2;
+
+    if (arrayPtr != NULL) {
+	TclDecrRefCount(arrayPtr);
+	ckfree(elem);
+    }
+    objPtr->typePtr = NULL;
+}
+
+static void
+DupParsedVarName(
+    Tcl_Obj *srcPtr,
+    Tcl_Obj *dupPtr)
+{
+    register Tcl_Obj *arrayPtr = srcPtr->internalRep.twoPtrValue.ptr1;
+    register char *elem = srcPtr->internalRep.twoPtrValue.ptr2;
+    char *elemCopy;
+    unsigned elemLen;
+
+    if (arrayPtr != NULL) {
+	Tcl_IncrRefCount(arrayPtr);
+	elemLen = strlen(elem);
+	elemCopy = ckalloc(elemLen + 1);
+	memcpy(elemCopy, elem, elemLen);
+	*(elemCopy + elemLen) = '\0';
+	elem = elemCopy;
+    }
+
+    dupPtr->internalRep.twoPtrValue.ptr1 = arrayPtr;
+    dupPtr->internalRep.twoPtrValue.ptr2 = elem;
+    dupPtr->typePtr = &tclParsedVarNameType;
+}
+
+static void
+UpdateParsedVarName(
+    Tcl_Obj *objPtr)
+{
+    Tcl_Obj *arrayPtr = objPtr->internalRep.twoPtrValue.ptr1;
+    char *part2 = objPtr->internalRep.twoPtrValue.ptr2;
+    const char *part1;
+    char *p;
+    int len1, len2, totalLen;
+
+    if (arrayPtr == NULL) {
+	/*
+	 * This is a parsed scalar name: what is it doing here?
+	 */
+
+	Tcl_Panic("scalar parsedVarName without a string rep");
+    }
+
+    part1 = TclGetStringFromObj(arrayPtr, &len1);
+    len2 = strlen(part2);
+
+    totalLen = len1 + len2 + 2;
+    p = ckalloc(totalLen + 1);
+    objPtr->bytes = p;
+    objPtr->length = totalLen;
+
+    memcpy(p, part1, (unsigned) len1);
+    p += len1;
+    *p++ = '(';
+    memcpy(p, part2, (unsigned) len2);
+    p += len2;
+    *p++ = ')';
+    *p = '\0';
+}
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * Tcl_FindNamespaceVar -- MOVED OVER from tclNamesp.c
+ *
+ *	Searches for a namespace variable, a variable not local to a
+ *	procedure. The variable can be either a scalar or an array, but may
+ *	not be an element of an array.
+ *
+ * Results:
+ *	Returns a token for the variable if it is found. Otherwise, if it
+ *	can't be found or there is an error, returns NULL and leaves an error
+ *	message in the interpreter's result object if "flags" contains
+ *	TCL_LEAVE_ERR_MSG.
+ *
+ * Side effects:
+ *	None.
+ *
+ *----------------------------------------------------------------------
+ */
+
+Tcl_Var
+Tcl_FindNamespaceVar(
+    Tcl_Interp *interp,		/* The interpreter in which to find the
+				 * variable. */
+    const char *name,		/* Variable's name. If it starts with "::",
+				 * will be looked up in global namespace.
+				 * Else, looked up first in contextNsPtr
+				 * (current namespace if contextNsPtr is
+				 * NULL), then in global namespace. */
+    Tcl_Namespace *contextNsPtr,/* Ignored if TCL_GLOBAL_ONLY flag set.
+				 * Otherwise, points to namespace in which to
+				 * resolve name. If NULL, look up name in the
+				 * current namespace. */
+    int flags)			/* An OR'd combination of:
+				 * TCL_AVOID_RESOLVERS, TCL_GLOBAL_ONLY (look
+				 * up name only in global namespace),
+				 * TCL_NAMESPACE_ONLY (look up only in
+				 * contextNsPtr, or the current namespace if
+				 * contextNsPtr is NULL), and
+				 * TCL_LEAVE_ERR_MSG. If both TCL_GLOBAL_ONLY
+				 * and TCL_NAMESPACE_ONLY are given,
+				 * TCL_GLOBAL_ONLY is ignored. */
+{
+    Tcl_Obj *namePtr = Tcl_NewStringObj(name, -1);
+    Tcl_Var var;
+
+    var = ObjFindNamespaceVar(interp, namePtr, contextNsPtr, flags);
+    Tcl_DecrRefCount(namePtr);
+    return var;
+}
+
+static Tcl_Var
+ObjFindNamespaceVar(
+    Tcl_Interp *interp,		/* The interpreter in which to find the
+				 * variable. */
+    Tcl_Obj *namePtr,		/* Variable's name. If it starts with "::",
+				 * will be looked up in global namespace.
+				 * Else, looked up first in contextNsPtr
+				 * (current namespace if contextNsPtr is
+				 * NULL), then in global namespace. */
+    Tcl_Namespace *contextNsPtr,/* Ignored if TCL_GLOBAL_ONLY flag set.
+				 * Otherwise, points to namespace in which to
+				 * resolve name. If NULL, look up name in the
+				 * current namespace. */
+    int flags)			/* An OR'd combination of:
+				 * TCL_AVOID_RESOLVERS, TCL_GLOBAL_ONLY (look
+				 * up name only in global namespace),
+				 * TCL_NAMESPACE_ONLY (look up only in
+				 * contextNsPtr, or the current namespace if
+				 * contextNsPtr is NULL), and
+				 * TCL_LEAVE_ERR_MSG. If both TCL_GLOBAL_ONLY
+				 * and TCL_NAMESPACE_ONLY are given,
+				 * TCL_GLOBAL_ONLY is ignored. */
+{
+    Interp *iPtr = (Interp *) interp;
+    ResolverScheme *resPtr;
+    Namespace *nsPtr[2], *cxtNsPtr;
+    const char *simpleName;
+    Var *varPtr;
+    register int search;
+    int result;
+    Tcl_Var var;
+    Tcl_Obj *simpleNamePtr;
+    const char *name = TclGetString(namePtr);
+
+    /*
+     * If this namespace has a variable resolver, then give it first crack at
+     * the variable resolution. It may return a Tcl_Var value, it may signal
+     * to continue onward, or it may signal an error.
+     */
+
+    if ((flags & TCL_GLOBAL_ONLY) != 0) {
+	cxtNsPtr = (Namespace *) TclGetGlobalNamespace(interp);
+    } else if (contextNsPtr != NULL) {
+	cxtNsPtr = (Namespace *) contextNsPtr;
+    } else {
+	cxtNsPtr = (Namespace *) TclGetCurrentNamespace(interp);
+    }
+
+    if (!(flags & TCL_AVOID_RESOLVERS) &&
+	    (cxtNsPtr->varResProc != NULL || iPtr->resolverPtr != NULL)) {
+	resPtr = iPtr->resolverPtr;
+
+	if (cxtNsPtr->varResProc) {
+	    result = cxtNsPtr->varResProc(interp, name,
+		    (Tcl_Namespace *) cxtNsPtr, flags, &var);
+	} else {
+	    result = TCL_CONTINUE;
+	}
+
+	while (result == TCL_CONTINUE && resPtr) {
+	    if (resPtr->varResProc) {
+		result = resPtr->varResProc(interp, name,
+			(Tcl_Namespace *) cxtNsPtr, flags, &var);
+	    }
+	    resPtr = resPtr->nextPtr;
+	}
+
+	if (result == TCL_OK) {
+	    return var;
+	} else if (result != TCL_CONTINUE) {
+	    return NULL;
+	}
+    }
+
+    /*
+     * Find the namespace(s) that contain the variable.
+     */
+
+    TclGetNamespaceForQualName(interp, name, (Namespace *) contextNsPtr,
+	    flags, &nsPtr[0], &nsPtr[1], &cxtNsPtr, &simpleName);
+
+    /*
+     * Look for the variable in the variable table of its namespace. Be sure
+     * to check both possible search paths: from the specified namespace
+     * context and from the global namespace.
+     */
+
+    varPtr = NULL;
+    if (simpleName != name) {
+	simpleNamePtr = Tcl_NewStringObj(simpleName, -1);
+    } else {
+	simpleNamePtr = namePtr;
+    }
+
+    for (search = 0;  (search < 2) && (varPtr == NULL);  search++) {
+	if ((nsPtr[search] != NULL) && (simpleName != NULL)) {
+	    varPtr = VarHashFindVar(&nsPtr[search]->varTable, simpleNamePtr);
+	}
+    }
+    if (simpleName != name) {
+	Tcl_DecrRefCount(simpleNamePtr);
+    }
+    if ((varPtr == NULL) && (flags & TCL_LEAVE_ERR_MSG)) {
+	Tcl_SetObjResult(interp, Tcl_ObjPrintf(
+		"unknown variable \"%s\"", name));
+	Tcl_SetErrorCode(interp, "TCL", "LOOKUP", "VARIABLE", name, NULL);
+    }
+    return (Tcl_Var) varPtr;
+}
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * InfoVarsCmd -- (moved over from tclCmdIL.c)
+ *
+ *	Called to implement the "info vars" command that returns the list of
+ *	variables in the interpreter that match an optional pattern. The
+ *	pattern, if any, consists of an optional sequence of namespace names
+ *	separated by "::" qualifiers, which is followed by a glob-style
+ *	pattern that restricts which variables are returned. Handles the
+ *	following syntax:
+ *
+ *	    info vars ?pattern?
+ *
+ * Results:
+ *	Returns TCL_OK if successful and TCL_ERROR if there is an error.
+ *
+ * Side effects:
+ *	Returns a result in the interpreter's result object. If there is an
+ *	error, the result is an error message.
+ *
+ *----------------------------------------------------------------------
+ */
+
+int
+TclInfoVarsCmd(
+    ClientData dummy,		/* Not used. */
+    Tcl_Interp *interp,		/* Current interpreter. */
+    int objc,			/* Number of arguments. */
+    Tcl_Obj *const objv[])	/* Argument objects. */
+{
+    Interp *iPtr = (Interp *) interp;
+    const char *varName, *pattern, *simplePattern;
+    Tcl_HashSearch search;
+    Var *varPtr;
+    Namespace *nsPtr;
+    Namespace *globalNsPtr = (Namespace *) Tcl_GetGlobalNamespace(interp);
+    Namespace *currNsPtr = (Namespace *) Tcl_GetCurrentNamespace(interp);
+    Tcl_Obj *listPtr, *elemObjPtr, *varNamePtr;
+    int specificNsInPattern = 0;/* Init. to avoid compiler warning. */
+    Tcl_Obj *simplePatternPtr = NULL;
+
+    /*
+     * Get the pattern and find the "effective namespace" in which to list
+     * variables. We only use this effective namespace if there's no active
+     * Tcl procedure frame.
+     */
+
+    if (objc == 1) {
+	simplePattern = NULL;
+	nsPtr = currNsPtr;
+	specificNsInPattern = 0;
+    } else if (objc == 2) {
+	/*
+	 * From the pattern, get the effective namespace and the simple
+	 * pattern (no namespace qualifiers or ::'s) at the end. If an error
+	 * was found while parsing the pattern, return it. Otherwise, if the
+	 * namespace wasn't found, just leave nsPtr NULL: we will return an
+	 * empty list since no variables there can be found.
+	 */
+
+	Namespace *dummy1NsPtr, *dummy2NsPtr;
+
+	pattern = TclGetString(objv[1]);
+	TclGetNamespaceForQualName(interp, pattern, NULL, /*flags*/ 0,
+		&nsPtr, &dummy1NsPtr, &dummy2NsPtr, &simplePattern);
+
+	if (nsPtr != NULL) {	/* We successfully found the pattern's ns. */
+	    specificNsInPattern = (strcmp(simplePattern, pattern) != 0);
+	    if (simplePattern == pattern) {
+		simplePatternPtr = objv[1];
+	    } else {
+		simplePatternPtr = Tcl_NewStringObj(simplePattern, -1);
+	    }
+	    Tcl_IncrRefCount(simplePatternPtr);
+	}
+    } else {
+	Tcl_WrongNumArgs(interp, 1, objv, "?pattern?");
+	return TCL_ERROR;
+    }
+
+    /*
+     * If the namespace specified in the pattern wasn't found, just return.
+     */
+
+    if (nsPtr == NULL) {
+	return TCL_OK;
+    }
+
+    listPtr = Tcl_NewListObj(0, NULL);
+
+    if (!HasLocalVars(iPtr->varFramePtr) || specificNsInPattern) {
+	/*
+	 * There is no frame pointer, the frame pointer was pushed only to
+	 * activate a namespace, or we are in a procedure call frame but a
+	 * specific namespace was specified. Create a list containing only the
+	 * variables in the effective namespace's variable table.
+	 */
+
+	if (simplePattern && TclMatchIsTrivial(simplePattern)) {
+	    /*
+	     * If we can just do hash lookups, that simplifies things a lot.
+	     */
+
+	    varPtr = VarHashFindVar(&nsPtr->varTable, simplePatternPtr);
+	    if (varPtr) {
+		if (!TclIsVarUndefined(varPtr)
+			|| TclIsVarNamespaceVar(varPtr)) {
+		    if (specificNsInPattern) {
+			elemObjPtr = Tcl_NewObj();
+			Tcl_GetVariableFullName(interp, (Tcl_Var) varPtr,
+				elemObjPtr);
+		    } else {
+			elemObjPtr = VarHashGetKey(varPtr);
+		    }
+		    Tcl_ListObjAppendElement(interp, listPtr, elemObjPtr);
+		}
+	    } else if ((nsPtr != globalNsPtr) && !specificNsInPattern) {
+		varPtr = VarHashFindVar(&globalNsPtr->varTable,
+			simplePatternPtr);
+		if (varPtr) {
+		    if (!TclIsVarUndefined(varPtr)
+			    || TclIsVarNamespaceVar(varPtr)) {
+			Tcl_ListObjAppendElement(interp, listPtr,
+				VarHashGetKey(varPtr));
+		    }
+		}
+	    }
+	} else {
+	    /*
+	     * Have to scan the tables of variables.
+	     */
+
+	    varPtr = VarHashFirstVar(&nsPtr->varTable, &search);
+	    while (varPtr) {
+		if (!TclIsVarUndefined(varPtr)
+			|| TclIsVarNamespaceVar(varPtr)) {
+		    varNamePtr = VarHashGetKey(varPtr);
+		    varName = TclGetString(varNamePtr);
+		    if ((simplePattern == NULL)
+			    || Tcl_StringMatch(varName, simplePattern)) {
+			if (specificNsInPattern) {
+			    elemObjPtr = Tcl_NewObj();
+			    Tcl_GetVariableFullName(interp, (Tcl_Var) varPtr,
+				    elemObjPtr);
+			} else {
+			    elemObjPtr = varNamePtr;
+			}
+			Tcl_ListObjAppendElement(interp, listPtr, elemObjPtr);
+		    }
+		}
+		varPtr = VarHashNextVar(&search);
+	    }
+
+	    /*
+	     * If the effective namespace isn't the global :: namespace, and a
+	     * specific namespace wasn't requested in the pattern (i.e., the
+	     * pattern only specifies variable names), then add in all global
+	     * :: variables that match the simple pattern. Of course, add in
+	     * only those variables that aren't hidden by a variable in the
+	     * effective namespace.
+	     */
+
+	    if ((nsPtr != globalNsPtr) && !specificNsInPattern) {
+		varPtr = VarHashFirstVar(&globalNsPtr->varTable,&search);
+		while (varPtr) {
+		    if (!TclIsVarUndefined(varPtr)
+			    || TclIsVarNamespaceVar(varPtr)) {
+			varNamePtr = VarHashGetKey(varPtr);
+			varName = TclGetString(varNamePtr);
+			if ((simplePattern == NULL)
+				|| Tcl_StringMatch(varName, simplePattern)) {
+			    if (VarHashFindVar(&nsPtr->varTable,
+				    varNamePtr) == NULL) {
+				Tcl_ListObjAppendElement(interp, listPtr,
+					varNamePtr);
+			    }
+			}
+		    }
+		    varPtr = VarHashNextVar(&search);
+		}
+	    }
+	}
+    } else if (iPtr->varFramePtr->procPtr != NULL) {
+	AppendLocals(interp, listPtr, simplePatternPtr, 1);
+    }
+
+    if (simplePatternPtr) {
+	Tcl_DecrRefCount(simplePatternPtr);
+    }
+    Tcl_SetObjResult(interp, listPtr);
+    return TCL_OK;
+}
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * InfoGlobalsCmd -- (moved over from tclCmdIL.c)
+ *
+ *	Called to implement the "info globals" command that returns the list
+ *	of global variables matching an optional pattern. Handles the
+ *	following syntax:
+ *
+ *	    info globals ?pattern?
+ *
+ * Results:
+ *	Returns TCL_OK if successful and TCL_ERROR if there is an error.
+ *
+ * Side effects:
+ *	Returns a result in the interpreter's result object. If there is an
+ *	error, the result is an error message.
+ *
+ *----------------------------------------------------------------------
+ */
+
+int
+TclInfoGlobalsCmd(
+    ClientData dummy,		/* Not used. */
+    Tcl_Interp *interp,		/* Current interpreter. */
+    int objc,			/* Number of arguments. */
+    Tcl_Obj *const objv[])	/* Argument objects. */
+{
+    const char *varName, *pattern;
+    Namespace *globalNsPtr = (Namespace *) Tcl_GetGlobalNamespace(interp);
+    Tcl_HashSearch search;
+    Var *varPtr;
+    Tcl_Obj *listPtr, *varNamePtr, *patternPtr;
+
+    if (objc == 1) {
+	pattern = NULL;
+    } else if (objc == 2) {
+	pattern = TclGetString(objv[1]);
+
+	/*
+	 * Strip leading global-namespace qualifiers. [Bug 1057461]
+	 */
+
+	if (pattern[0] == ':' && pattern[1] == ':') {
+	    while (*pattern == ':') {
+		pattern++;
+	    }
+	}
+    } else {
+	Tcl_WrongNumArgs(interp, 1, objv, "?pattern?");
+	return TCL_ERROR;
+    }
+
+    /*
+     * Scan through the global :: namespace's variable table and create a list
+     * of all global variables that match the pattern.
+     */
+
+    listPtr = Tcl_NewListObj(0, NULL);
+    if (pattern != NULL && TclMatchIsTrivial(pattern)) {
+	if (pattern == TclGetString(objv[1])) {
+	    patternPtr = objv[1];
+	} else {
+	    patternPtr = Tcl_NewStringObj(pattern, -1);
+	}
+	Tcl_IncrRefCount(patternPtr);
+
+	varPtr = VarHashFindVar(&globalNsPtr->varTable, patternPtr);
+	if (varPtr) {
+	    if (!TclIsVarUndefined(varPtr)) {
+		Tcl_ListObjAppendElement(interp, listPtr,
+			VarHashGetKey(varPtr));
+	    }
+	}
+	Tcl_DecrRefCount(patternPtr);
+    } else {
+	for (varPtr = VarHashFirstVar(&globalNsPtr->varTable, &search);
+		varPtr != NULL;
+		varPtr = VarHashNextVar(&search)) {
+	    if (TclIsVarUndefined(varPtr)) {
+		continue;
+	    }
+	    varNamePtr = VarHashGetKey(varPtr);
+	    varName = TclGetString(varNamePtr);
+	    if ((pattern == NULL) || Tcl_StringMatch(varName, pattern)) {
+		Tcl_ListObjAppendElement(interp, listPtr, varNamePtr);
+	    }
+	}
+    }
+    Tcl_SetObjResult(interp, listPtr);
+    return TCL_OK;
+}
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * TclInfoLocalsCmd -- (moved over from tclCmdIl.c)
+ *
+ *	Called to implement the "info locals" command to return a list of
+ *	local variables that match an optional pattern. Handles the following
+ *	syntax:
+ *
+ *	    info locals ?pattern?
+ *
+ * Results:
+ *	Returns TCL_OK if successful and TCL_ERROR if there is an error.
+ *
+ * Side effects:
+ *	Returns a result in the interpreter's result object. If there is an
+ *	error, the result is an error message.
+ *
+ *----------------------------------------------------------------------
+ */
+
+int
+TclInfoLocalsCmd(
+    ClientData dummy,		/* Not used. */
+    Tcl_Interp *interp,		/* Current interpreter. */
+    int objc,			/* Number of arguments. */
+    Tcl_Obj *const objv[])	/* Argument objects. */
+{
+    Interp *iPtr = (Interp *) interp;
+    Tcl_Obj *patternPtr, *listPtr;
+
+    if (objc == 1) {
+	patternPtr = NULL;
+    } else if (objc == 2) {
+	patternPtr = objv[1];
+    } else {
+	Tcl_WrongNumArgs(interp, 1, objv, "?pattern?");
+	return TCL_ERROR;
+    }
+
+    if (!HasLocalVars(iPtr->varFramePtr)) {
+	return TCL_OK;
+    }
+
+    /*
+     * Return a list containing names of first the compiled locals (i.e. the
+     * ones stored in the call frame), then the variables in the local hash
+     * table (if one exists).
+     */
+
+    listPtr = Tcl_NewListObj(0, NULL);
+    AppendLocals(interp, listPtr, patternPtr, 0);
+    Tcl_SetObjResult(interp, listPtr);
+    return TCL_OK;
+}
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * AppendLocals --
+ *
+ *	Append the local variables for the current frame to the specified list
+ *	object.
+ *
+ * Results:
+ *	None.
+ *
+ * Side effects:
+ *	None.
+ *
+ *----------------------------------------------------------------------
+ */
+
+static void
+AppendLocals(
+    Tcl_Interp *interp,		/* Current interpreter. */
+    Tcl_Obj *listPtr,		/* List object to append names to. */
+    Tcl_Obj *patternPtr,	/* Pattern to match against. */
+    int includeLinks)		/* 1 if upvars should be included, else 0. */
+{
+    Interp *iPtr = (Interp *) interp;
+    Var *varPtr;
+    int i, localVarCt, added;
+    Tcl_Obj **varNamePtr, *objNamePtr;
+    const char *varName;
+    TclVarHashTable *localVarTablePtr;
+    Tcl_HashSearch search;
+    Tcl_HashTable addedTable;
+    const char *pattern = patternPtr? TclGetString(patternPtr) : NULL;
+
+    localVarCt = iPtr->varFramePtr->numCompiledLocals;
+    varPtr = iPtr->varFramePtr->compiledLocals;
+    localVarTablePtr = iPtr->varFramePtr->varTablePtr;
+    varNamePtr = &iPtr->varFramePtr->localCachePtr->varName0;
+    if (includeLinks) {
+	Tcl_InitObjHashTable(&addedTable);
+    }
+
+    for (i = 0; i < localVarCt; i++, varNamePtr++) {
+	/*
+	 * Skip nameless (temporary) variables and undefined variables.
+	 */
+
+	if (*varNamePtr && !TclIsVarUndefined(varPtr)
+		&& (includeLinks || !TclIsVarLink(varPtr))) {
+	    varName = TclGetString(*varNamePtr);
+	    if ((pattern == NULL) || Tcl_StringMatch(varName, pattern)) {
+		Tcl_ListObjAppendElement(interp, listPtr, *varNamePtr);
+		if (includeLinks) {
+		    Tcl_CreateHashEntry(&addedTable, *varNamePtr, &added);
+		}
+	    }
+	}
+	varPtr++;
+    }
+
+    /*
+     * Do nothing if no local variables.
+     */
+
+    if (localVarTablePtr == NULL) {
+	goto objectVars;
+    }
+
+    /*
+     * Check for the simple and fast case.
+     */
+
+    if ((pattern != NULL) && TclMatchIsTrivial(pattern)) {
+	varPtr = VarHashFindVar(localVarTablePtr, patternPtr);
+	if (varPtr != NULL) {
+	    if (!TclIsVarUndefined(varPtr)
+		    && (includeLinks || !TclIsVarLink(varPtr))) {
+		Tcl_ListObjAppendElement(interp, listPtr,
+			VarHashGetKey(varPtr));
+		if (includeLinks) {
+		    Tcl_CreateHashEntry(&addedTable, VarHashGetKey(varPtr),
+			    &added);
+		}
+	    }
+	}
+	goto objectVars;
+    }
+
+    /*
+     * Scan over and process all local variables.
+     */
+
+    for (varPtr = VarHashFirstVar(localVarTablePtr, &search);
+	    varPtr != NULL;
+	    varPtr = VarHashNextVar(&search)) {
+	if (!TclIsVarUndefined(varPtr)
+		&& (includeLinks || !TclIsVarLink(varPtr))) {
+	    objNamePtr = VarHashGetKey(varPtr);
+	    varName = TclGetString(objNamePtr);
+	    if ((pattern == NULL) || Tcl_StringMatch(varName, pattern)) {
+		Tcl_ListObjAppendElement(interp, listPtr, objNamePtr);
+		if (includeLinks) {
+		    Tcl_CreateHashEntry(&addedTable, objNamePtr, &added);
+		}
+	    }
+	}
+    }
+
+  objectVars:
+    if (!includeLinks) {
+	return;
+    }
+
+    if (iPtr->varFramePtr->isProcCallFrame & FRAME_IS_METHOD) {
+	CallContext *contextPtr = iPtr->varFramePtr->clientData;
+	Method *mPtr = contextPtr->callPtr->chain[contextPtr->index].mPtr;
+
+	if (mPtr->declaringObjectPtr) {
+	    FOREACH(objNamePtr, mPtr->declaringObjectPtr->variables) {
+		Tcl_CreateHashEntry(&addedTable, objNamePtr, &added);
+		if (added && (!pattern ||
+			Tcl_StringMatch(TclGetString(objNamePtr), pattern))) {
+		    Tcl_ListObjAppendElement(interp, listPtr, objNamePtr);
+		}
+	    }
+	} else {
+	    FOREACH(objNamePtr, mPtr->declaringClassPtr->variables) {
+		Tcl_CreateHashEntry(&addedTable, objNamePtr, &added);
+		if (added && (!pattern ||
+			Tcl_StringMatch(TclGetString(objNamePtr), pattern))) {
+		    Tcl_ListObjAppendElement(interp, listPtr, objNamePtr);
+		}
+	    }
+	}
+    }
+    Tcl_DeleteHashTable(&addedTable);
+}
+
+/*
+ * Hash table implementation - first, just copy and adapt the obj key stuff
+ */
+
+void
+TclInitVarHashTable(
+    TclVarHashTable *tablePtr,
+    Namespace *nsPtr)
+{
+    Tcl_InitCustomHashTable(&tablePtr->table,
+	    TCL_CUSTOM_TYPE_KEYS, &tclVarHashKeyType);
+    tablePtr->nsPtr = nsPtr;
+}
+
+static Tcl_HashEntry *
+AllocVarEntry(
+    Tcl_HashTable *tablePtr,	/* Hash table. */
+    void *keyPtr)		/* Key to store in the hash table entry. */
+{
+    Tcl_Obj *objPtr = keyPtr;
+    Tcl_HashEntry *hPtr;
+    Var *varPtr;
+
+    varPtr = ckalloc(sizeof(VarInHash));
+    varPtr->flags = VAR_IN_HASHTABLE;
+    varPtr->value.objPtr = NULL;
+    VarHashRefCount(varPtr) = 1;
+
+    hPtr = &(((VarInHash *) varPtr)->entry);
+    Tcl_SetHashValue(hPtr, varPtr);
+    hPtr->key.objPtr = objPtr;
+    Tcl_IncrRefCount(objPtr);
+
+    return hPtr;
+}
+
+static void
+FreeVarEntry(
+    Tcl_HashEntry *hPtr)
+{
+    Var *varPtr = VarHashGetValue(hPtr);
+    Tcl_Obj *objPtr = hPtr->key.objPtr;
+
+    if (TclIsVarUndefined(varPtr) && !TclIsVarTraced(varPtr)
+	    && (VarHashRefCount(varPtr) == 1)) {
+	ckfree(varPtr);
+    } else {
+	VarHashInvalidateEntry(varPtr);
+	TclSetVarUndefined(varPtr);
+	VarHashRefCount(varPtr)--;
+    }
+    Tcl_DecrRefCount(objPtr);
+}
+
+static int
+CompareVarKeys(
+    void *keyPtr,		/* New key to compare. */
+    Tcl_HashEntry *hPtr)	/* Existing key to compare. */
+{
+    Tcl_Obj *objPtr1 = keyPtr;
+    Tcl_Obj *objPtr2 = hPtr->key.objPtr;
+    register const char *p1, *p2;
+    register int l1, l2;
+
+    /*
+     * If the object pointers are the same then they match.
+     * OPT: this comparison was moved to the caller
+
+       if (objPtr1 == objPtr2) return 1;
+    */
+
+    /*
+     * Don't use Tcl_GetStringFromObj as it would prevent l1 and l2 being in a
+     * register.
+     */
+
+    p1 = TclGetString(objPtr1);
+    l1 = objPtr1->length;
+    p2 = TclGetString(objPtr2);
+    l2 = objPtr2->length;
+
+    /*
+     * Only compare string representations of the same length.
+     */
+
+    return ((l1 == l2) && !memcmp(p1, p2, l1));
+}
+
+/*
+ * Local Variables:
+ * mode: c
+ * c-basic-offset: 4
+ * fill-column: 78
+ * End:
+ */