Merge 8.7

6 files changed, 1232 insertions, 42 deletions

diff --git a/generic/tclOO.c b/generic/tclOO.c
index b05fe1f..8bf29fe 100644
--- a/generic/tclOO.c
+++ b/generic/tclOO.c
@@ -3,7 +3,7 @@
  *
  *	This file contains the object-system core (NB: not Tcl_Obj, but ::oo)
  *
- * Copyright © 2005-2012 Donal K. Fellows
+ * Copyright © 2005-2019 Donal K. Fellows
  * Copyright © 2017 Nathan Coulter
  *
  * See the file "license.terms" for information on usage and redistribution of
@@ -327,6 +327,7 @@ InitFoundation(
 	    DeletedObjdefNamespace);
     fPtr->helpersNs = Tcl_CreateNamespace(interp, "::oo::Helpers", fPtr,
 	    DeletedHelpersNamespace);
+    Tcl_CreateNamespace(interp, "::oo::configuresupport", NULL, NULL);
     fPtr->epoch = 1;
     fPtr->tsdPtr = tsdPtr;
     TclNewLiteralStringObj(fPtr->unknownMethodNameObj, "unknown");
@@ -964,7 +965,7 @@ TclOOReleaseClassContents(
     Class *clsPtr = oPtr->classPtr, *tmpClsPtr;
     Method *mPtr;
     Foundation *fPtr = oPtr->fPtr;
-    Tcl_Obj *variableObj;
+    Tcl_Obj *variableObj, *propertyObj;
     PrivateVariableMapping *privateVariable;
 
     /*
@@ -1018,6 +1019,29 @@ TclOOReleaseClassContents(
     }
 
     /*
+     * Squelch the property lists.
+     */
+
+    if (clsPtr->properties.allReadableCache) {
+	Tcl_DecrRefCount(clsPtr->properties.allReadableCache);
+    }
+    if (clsPtr->properties.allWritableCache) {
+	Tcl_DecrRefCount(clsPtr->properties.allWritableCache);
+    }
+    if (clsPtr->properties.readable.num) {
+	FOREACH(propertyObj, clsPtr->properties.readable) {
+	    Tcl_DecrRefCount(propertyObj);
+	}
+	ckfree(clsPtr->properties.readable.list);
+    }
+    if (clsPtr->properties.writable.num) {
+	FOREACH(propertyObj, clsPtr->properties.writable) {
+	    Tcl_DecrRefCount(propertyObj);
+	}
+	ckfree(clsPtr->properties.writable.list);
+    }
+
+    /*
      * Squelch our filter list.
      */
 
@@ -1118,7 +1142,7 @@ ObjectNamespaceDeleted(
     FOREACH_HASH_DECLS;
     Class *mixinPtr;
     Method *mPtr;
-    Tcl_Obj *filterObj, *variableObj;
+    Tcl_Obj *filterObj, *variableObj, *propertyObj;
     PrivateVariableMapping *privateVariable;
     Tcl_Interp *interp = oPtr->fPtr->interp;
     Tcl_Size i;
@@ -1272,6 +1296,29 @@ ObjectNamespaceDeleted(
     }
 
     /*
+     * Squelch the property lists.
+     */
+
+    if (oPtr->properties.allReadableCache) {
+	Tcl_DecrRefCount(oPtr->properties.allReadableCache);
+    }
+    if (oPtr->properties.allWritableCache) {
+	Tcl_DecrRefCount(oPtr->properties.allWritableCache);
+    }
+    if (oPtr->properties.readable.num) {
+	FOREACH(propertyObj, oPtr->properties.readable) {
+	    Tcl_DecrRefCount(propertyObj);
+	}
+	ckfree(oPtr->properties.readable.list);
+    }
+    if (oPtr->properties.writable.num) {
+	FOREACH(propertyObj, oPtr->properties.writable) {
+	    Tcl_DecrRefCount(propertyObj);
+	}
+	ckfree(oPtr->properties.writable.list);
+    }
+
+    /*
      * Because an object can be a class that is an instance of itself, the
      * class object's class structure should only be cleaned after most of
      * the cleanup on the object is done.
diff --git a/generic/tclOOCall.c b/generic/tclOOCall.c
index 5c9c986..39fd020 100644
--- a/generic/tclOOCall.c
+++ b/generic/tclOOCall.c
@@ -2,9 +2,10 @@
  * tclOOCall.c --
  *
  *	This file contains the method call chain management code for the
- *	object-system core.
+ *	object-system core. It also contains everything else that does
+ *	inheritance hierarchy traversal.
  *
- * Copyright © 2005-2012 Donal K. Fellows
+ * Copyright © 2005-2019 Donal K. Fellows
  *
  * See the file "license.terms" for information on usage and redistribution of
  * this file, and for a DISCLAIMER OF ALL WARRANTIES.
@@ -58,6 +59,7 @@ typedef struct {
 #define BUILDING_MIXINS	   0x400000
 #define TRAVERSED_MIXIN	   0x800000
 #define OBJECT_MIXIN	   0x1000000
+#define DEFINE_FOR_CLASS   0x2000000
 #define MIXIN_CONSISTENT(flags) \
     (((flags) & OBJECT_MIXIN) ||					\
 	!((flags) & BUILDING_MIXINS) == !((flags) & TRAVERSED_MIXIN))
@@ -1907,7 +1909,7 @@ TclOOGetDefineContextNamespace(
     DefineEntry staticSpace[DEFINE_CHAIN_STATIC_SIZE];
     DefineEntry *entryPtr;
     Tcl_Namespace *nsPtr = NULL;
-    int i;
+    int i, flags = (forClass ? DEFINE_FOR_CLASS : 0);
 
     define.list = staticSpace;
     define.num = 0;
@@ -1918,8 +1920,8 @@ TclOOGetDefineContextNamespace(
      * class mixins right.
      */
 
-    AddSimpleDefineNamespaces(oPtr, &define, forClass | BUILDING_MIXINS);
-    AddSimpleDefineNamespaces(oPtr, &define, forClass);
+    AddSimpleDefineNamespaces(oPtr, &define, flags | BUILDING_MIXINS);
+    AddSimpleDefineNamespaces(oPtr, &define, flags);
 
     /*
      * Go through the list until we find a namespace whose name we can
@@ -2003,7 +2005,7 @@ AddSimpleClassDefineNamespaces(
 		flags | TRAVERSED_MIXIN);
     }
 
-    if (flags & ~(TRAVERSED_MIXIN | BUILDING_MIXINS)) {
+    if (flags & DEFINE_FOR_CLASS) {
 	AddDefinitionNamespaceToChain(classPtr, classPtr->clsDefinitionNs,
 		definePtr, flags);
     } else {
@@ -2113,6 +2115,259 @@ AddDefinitionNamespaceToChain(
 }
 
 /*
+ * ----------------------------------------------------------------------
+ *
+ * FindClassProps --
+ *
+ *	Discover the properties known to a class and its superclasses.
+ *	The property names become the keys in the accumulator hash table
+ *	(which is used as a set).
+ *
+ * ----------------------------------------------------------------------
+ */
+
+static void
+FindClassProps(
+    Class *clsPtr,		/* The object to inspect. Must exist. */
+    int writable,		/* Whether we're after the readable or writable
+				 * property set. */
+    Tcl_HashTable *accumulator)	/* Where to gather the names. */
+{
+    int i, dummy;
+    Tcl_Obj *propName;
+    Class *mixin, *sup;
+
+  tailRecurse:
+    if (writable) {
+	FOREACH(propName, clsPtr->properties.writable) {
+	    Tcl_CreateHashEntry(accumulator, (void *) propName, &dummy);
+	}
+    } else {
+	FOREACH(propName, clsPtr->properties.readable) {
+	    Tcl_CreateHashEntry(accumulator, (void *) propName, &dummy);
+	}
+    }
+    if (clsPtr->thisPtr->flags & ROOT_OBJECT) {
+	/*
+	 * We do *not* traverse upwards from the root!
+	 */
+	return;
+    }
+    FOREACH(mixin, clsPtr->mixins) {
+	FindClassProps(mixin, writable, accumulator);
+    }
+    if (clsPtr->superclasses.num == 1) {
+	clsPtr = clsPtr->superclasses.list[0];
+	goto tailRecurse;
+    }
+    FOREACH(sup, clsPtr->superclasses) {
+	FindClassProps(sup, writable, accumulator);
+    }
+}
+
+/*
+ * ----------------------------------------------------------------------
+ *
+ * FindObjectProps --
+ *
+ *	Discover the properties known to an object and all its classes.
+ *	The property names become the keys in the accumulator hash table
+ *	(which is used as a set).
+ *
+ * ----------------------------------------------------------------------
+ */
+
+static void
+FindObjectProps(
+    Object *oPtr,		/* The object to inspect. Must exist. */
+    int writable,		/* Whether we're after the readable or writable
+				 * property set. */
+    Tcl_HashTable *accumulator)	/* Where to gather the names. */
+{
+    int i, dummy;
+    Tcl_Obj *propName;
+    Class *mixin;
+
+    if (writable) {
+	FOREACH(propName, oPtr->properties.writable) {
+	    Tcl_CreateHashEntry(accumulator, (void *) propName, &dummy);
+	}
+    } else {
+	FOREACH(propName, oPtr->properties.readable) {
+	    Tcl_CreateHashEntry(accumulator, (void *) propName, &dummy);
+	}
+    }
+    FOREACH(mixin, oPtr->mixins) {
+	FindClassProps(mixin, writable, accumulator);
+    }
+    FindClassProps(oPtr->selfCls, writable, accumulator);
+}
+
+/*
+ * ----------------------------------------------------------------------
+ *
+ * TclOOGetAllClassProperties --
+ *
+ *	Get the list of all properties known to a class, including to its
+ *	superclasses. Manages a cache so this operation is usually cheap.
+ *	The order of properties in the resulting list is undefined.
+ *
+ * ----------------------------------------------------------------------
+ */
+
+Tcl_Obj *
+TclOOGetAllClassProperties(
+    Class *clsPtr,		/* The class to inspect. Must exist. */
+    int writable,		/* Whether to get writable properties. If
+				 * false, readable properties will be returned
+				 * instead. */
+    int *allocated)		/* Address of variable to set to true if a
+				 * Tcl_Obj was allocated and may be safely
+				 * modified by the caller. */
+{
+    Tcl_HashTable hashTable;
+    FOREACH_HASH_DECLS;
+    Tcl_Obj *propName, *result;
+    void *dummy;
+
+    /*
+     * Look in the cache.
+     */
+
+    if (clsPtr->properties.epoch == clsPtr->thisPtr->fPtr->epoch) {
+	if (writable) {
+	    if (clsPtr->properties.allWritableCache) {
+		*allocated = 0;
+		return clsPtr->properties.allWritableCache;
+	    }
+	} else {
+	    if (clsPtr->properties.allReadableCache) {
+		*allocated = 0;
+		return clsPtr->properties.allReadableCache;
+	    }
+	}
+    }
+
+    /*
+     * Gather the information. Unsorted! (Caller will sort.)
+     */
+
+    *allocated = 1;
+    Tcl_InitObjHashTable(&hashTable);
+    FindClassProps(clsPtr, writable, &hashTable);
+    result = Tcl_NewObj();
+    FOREACH_HASH(propName, dummy, &hashTable) {
+	Tcl_ListObjAppendElement(NULL, result, propName);
+    }
+    Tcl_DeleteHashTable(&hashTable);
+
+    /*
+     * Cache the information. Also purges the cache.
+     */
+
+    if (clsPtr->properties.epoch != clsPtr->thisPtr->fPtr->epoch) {
+	if (clsPtr->properties.allWritableCache) {
+	    Tcl_DecrRefCount(clsPtr->properties.allWritableCache);
+	    clsPtr->properties.allWritableCache = NULL;
+	}
+	if (clsPtr->properties.allReadableCache) {
+	    Tcl_DecrRefCount(clsPtr->properties.allReadableCache);
+	    clsPtr->properties.allReadableCache = NULL;
+	}
+    }
+    clsPtr->properties.epoch = clsPtr->thisPtr->fPtr->epoch;
+    if (writable) {
+	clsPtr->properties.allWritableCache = result;
+    } else {
+	clsPtr->properties.allReadableCache = result;
+    }
+    Tcl_IncrRefCount(result);
+    return result;
+}
+
+/*
+ * ----------------------------------------------------------------------
+ *
+ * TclOOGetAllObjectProperties --
+ *
+ *	Get the list of all properties known to a object, including to its
+ *	classes. Manages a cache so this operation is usually cheap.
+ *	The order of properties in the resulting list is undefined.
+ *
+ * ----------------------------------------------------------------------
+ */
+
+Tcl_Obj *
+TclOOGetAllObjectProperties(
+    Object *oPtr,		/* The object to inspect. Must exist. */
+    int writable,		/* Whether to get writable properties. If
+				 * false, readable properties will be returned
+				 * instead. */
+    int *allocated)		/* Address of variable to set to true if a
+				 * Tcl_Obj was allocated and may be safely
+				 * modified by the caller. */
+{
+    Tcl_HashTable hashTable;
+    FOREACH_HASH_DECLS;
+    Tcl_Obj *propName, *result;
+    void *dummy;
+
+    /*
+     * Look in the cache.
+     */
+
+    if (oPtr->properties.epoch == oPtr->fPtr->epoch) {
+	if (writable) {
+	    if (oPtr->properties.allWritableCache) {
+		*allocated = 0;
+		return oPtr->properties.allWritableCache;
+	    }
+	} else {
+	    if (oPtr->properties.allReadableCache) {
+		*allocated = 0;
+		return oPtr->properties.allReadableCache;
+	    }
+	}
+    }
+
+    /*
+     * Gather the information. Unsorted! (Caller will sort.)
+     */
+
+    *allocated = 1;
+    Tcl_InitObjHashTable(&hashTable);
+    FindObjectProps(oPtr, writable, &hashTable);
+    result = Tcl_NewObj();
+    FOREACH_HASH(propName, dummy, &hashTable) {
+	Tcl_ListObjAppendElement(NULL, result, propName);
+    }
+    Tcl_DeleteHashTable(&hashTable);
+
+    /*
+     * Cache the information.
+     */
+
+    if (oPtr->properties.epoch != oPtr->fPtr->epoch) {
+	if (oPtr->properties.allWritableCache) {
+	    Tcl_DecrRefCount(oPtr->properties.allWritableCache);
+	    oPtr->properties.allWritableCache = NULL;
+	}
+	if (oPtr->properties.allReadableCache) {
+	    Tcl_DecrRefCount(oPtr->properties.allReadableCache);
+	    oPtr->properties.allReadableCache = NULL;
+	}
+    }
+    oPtr->properties.epoch = oPtr->fPtr->epoch;
+    if (writable) {
+	oPtr->properties.allWritableCache = result;
+    } else {
+	oPtr->properties.allReadableCache = result;
+    }
+    Tcl_IncrRefCount(result);
+    return result;
+}
+
+/*
  * Local Variables:
  * mode: c
  * c-basic-offset: 4
diff --git a/generic/tclOODefineCmds.c b/generic/tclOODefineCmds.c
index 84204f9..8879e26 100644
--- a/generic/tclOODefineCmds.c
+++ b/generic/tclOODefineCmds.c
@@ -4,7 +4,7 @@
  *	This file contains the implementation of the ::oo::define command,
  *	part of the object-system core (NB: not Tcl_Obj, but ::oo).
  *
- * Copyright © 2006-2013 Donal K. Fellows
+ * Copyright © 2006-2019 Donal K. Fellows
  *
  * See the file "license.terms" for information on usage and redistribution of
  * this file, and for a DISCLAIMER OF ALL WARRANTIES.
@@ -60,6 +60,7 @@ struct DeclaredSlot {
  */
 
 static inline void	BumpGlobalEpoch(Tcl_Interp *interp, Class *classPtr);
+static inline void	BumpInstanceEpoch(Object *oPtr);
 static Tcl_Command	FindCommand(Tcl_Interp *interp, Tcl_Obj *stringObj,
 			    Tcl_Namespace *const namespacePtr);
 static inline void	GenerateErrorInfo(Tcl_Interp *interp, Object *oPtr,
@@ -102,6 +103,8 @@ static int		ClassVarsGet(void *clientData,
 static int		ClassVarsSet(void *clientData,
 			    Tcl_Interp *interp, Tcl_ObjectContext context,
 			    int objc, Tcl_Obj *const *objv);
+static Tcl_MethodCallProc ClassRPropsGet, ClassRPropsSet;
+static Tcl_MethodCallProc ClassWPropsGet, ClassWPropsSet;
 static int		ObjFilterGet(void *clientData,
 			    Tcl_Interp *interp, Tcl_ObjectContext context,
 			    int objc, Tcl_Obj *const *objv);
@@ -120,6 +123,8 @@ static int		ObjVarsGet(void *clientData,
 static int		ObjVarsSet(void *clientData,
 			    Tcl_Interp *interp, Tcl_ObjectContext context,
 			    int objc, Tcl_Obj *const *objv);
+static Tcl_MethodCallProc ObjRPropsGet, ObjRPropsSet;
+static Tcl_MethodCallProc ObjWPropsGet, ObjWPropsSet;
 static int		ResolveClass(void *clientData,
 			    Tcl_Interp *interp, Tcl_ObjectContext context,
 			    int objc, Tcl_Obj *const *objv);
@@ -136,6 +141,14 @@ static const struct DeclaredSlot slots[] = {
     SLOT("objdefine::filter",   ObjFilterGet,   ObjFilterSet, NULL),
     SLOT("objdefine::mixin",    ObjMixinGet,    ObjMixinSet, ResolveClass),
     SLOT("objdefine::variable", ObjVarsGet,     ObjVarsSet, NULL),
+    SLOT("configuresupport::readableproperties",
+	    ClassRPropsGet, ClassRPropsSet, NULL),
+    SLOT("configuresupport::writableproperties",
+	    ClassWPropsGet, ClassWPropsSet, NULL),
+    SLOT("configuresupport::objreadableproperties",
+	    ObjRPropsGet, ObjRPropsSet, NULL),
+    SLOT("configuresupport::objwritableproperties",
+	    ObjWPropsGet, ObjWPropsSet, NULL),
     {NULL, {0, 0, 0, 0, 0}, {0, 0, 0, 0, 0}, {0, 0, 0, 0, 0}}
 };
 
@@ -201,13 +214,26 @@ BumpGlobalEpoch(
 
 	if (classPtr->thisPtr->mixins.num > 0) {
 	    classPtr->thisPtr->epoch++;
+
+	    /*
+	     * Invalidate the property caches directly.
+	     */
+
+	    if (classPtr->properties.allReadableCache) {
+		Tcl_DecrRefCount(classPtr->properties.allReadableCache);
+		classPtr->properties.allReadableCache = NULL;
+	    }
+	    if (classPtr->properties.allWritableCache) {
+		Tcl_DecrRefCount(classPtr->properties.allWritableCache);
+		classPtr->properties.allWritableCache = NULL;
+	    }
 	}
 	return;
     }
 
     /*
      * Either there's no class (?!) or we're reconfiguring something that is
-     * in use. Force regeneration of call chains.
+     * in use. Force regeneration of call chains and properties.
      */
 
     TclOOGetFoundation(interp)->epoch++;
@@ -216,6 +242,33 @@ BumpGlobalEpoch(
 /*
  * ----------------------------------------------------------------------
  *
+ * BumpInstanceEpoch --
+ *
+ *	Advances the epoch and clears the property cache of an object. The
+ *	equivalent for classes is BumpGlobalEpoch(), as classes have a more
+ *	complex set of relationships to other entities.
+ *
+ * ----------------------------------------------------------------------
+ */
+
+static inline void
+BumpInstanceEpoch(
+    Object *oPtr)
+{
+    oPtr->epoch++;
+    if (oPtr->properties.allReadableCache) {
+	Tcl_DecrRefCount(oPtr->properties.allReadableCache);
+	oPtr->properties.allReadableCache = NULL;
+    }
+    if (oPtr->properties.allWritableCache) {
+	Tcl_DecrRefCount(oPtr->properties.allWritableCache);
+	oPtr->properties.allWritableCache = NULL;
+    }
+}
+
+/*
+ * ----------------------------------------------------------------------
+ *
  * RecomputeClassCacheFlag --
  *
  *	Determine whether the object is prototypical of its class, and hence
@@ -292,7 +345,7 @@ TclOOObjectSetFilters(
 	oPtr->filters.num = numFilters;
 	oPtr->flags &= ~USE_CLASS_CACHE;
     }
-    oPtr->epoch++;		/* Only this object can be affected. */
+    BumpInstanceEpoch(oPtr);	/* Only this object can be affected. */
 }
 
 /*
@@ -415,7 +468,7 @@ TclOOObjectSetMixins(
 	    }
 	}
     }
-    oPtr->epoch++;
+    BumpInstanceEpoch(oPtr);
 }
 
 /*
@@ -482,6 +535,7 @@ TclOOClassSetMixins(
  *
  * ----------------------------------------------------------------------
  */
+
 static inline void
 InstallStandardVariableMapping(
     VariableNameList *vnlPtr,
@@ -1507,7 +1561,7 @@ TclOODefineClassObjCmd(
 	if (oPtr->classPtr != NULL) {
 	    BumpGlobalEpoch(interp, oPtr->classPtr);
 	} else {
-	    oPtr->epoch++;
+	    BumpInstanceEpoch(oPtr);
 	}
     }
     return TCL_OK;
@@ -1717,7 +1771,7 @@ TclOODefineDeleteMethodObjCmd(
     }
 
     if (isInstanceDeleteMethod) {
-	oPtr->epoch++;
+	BumpInstanceEpoch(oPtr);
     } else {
 	BumpGlobalEpoch(interp, oPtr->classPtr);
     }
@@ -1877,7 +1931,7 @@ TclOODefineExportObjCmd(
 
     if (changed) {
 	if (isInstanceExport) {
-	    oPtr->epoch++;
+	    BumpInstanceEpoch(oPtr);
 	} else {
 	    BumpGlobalEpoch(interp, clsPtr);
 	}
@@ -2095,7 +2149,7 @@ TclOODefineRenameMethodObjCmd(
     }
 
     if (isInstanceRenameMethod) {
-	oPtr->epoch++;
+	BumpInstanceEpoch(oPtr);
     } else {
 	BumpGlobalEpoch(interp, oPtr->classPtr);
     }
@@ -2189,7 +2243,7 @@ TclOODefineUnexportObjCmd(
 
     if (changed) {
 	if (isInstanceUnexport) {
-	    oPtr->epoch++;
+	    BumpInstanceEpoch(oPtr);
 	} else {
 	    BumpGlobalEpoch(interp, clsPtr);
 	}
@@ -3082,6 +3136,398 @@ ResolveClass(
 }
 
 /*
+ * ----------------------------------------------------------------------
+ *
+ * ClassRPropsGet, ClassRPropsSet, ObjRPropsGet, ObjRPropsSet --
+ *
+ *	Implementations of the "readableproperties" slot accessors for classes
+ *	and instances.
+ *
+ * ----------------------------------------------------------------------
+ */
+
+static void
+InstallReadableProps(
+    PropertyStorage *props,
+    int objc,
+    Tcl_Obj *const objv[])
+{
+    Tcl_Obj *propObj;
+    int i, n, created;
+    Tcl_HashTable uniqueTable;
+
+    if (props->allReadableCache) {
+	Tcl_DecrRefCount(props->allReadableCache);
+	props->allReadableCache = NULL;
+    }
+
+    for (i=0 ; i<objc ; i++) {
+	Tcl_IncrRefCount(objv[i]);
+    }
+    FOREACH(propObj, props->readable) {
+	Tcl_DecrRefCount(propObj);
+    }
+    if (i != objc) {
+	if (objc == 0) {
+	    ckfree(props->readable.list);
+	} else if (i) {
+	    props->readable.list = (Tcl_Obj **)ckrealloc(props->readable.list,
+		    sizeof(Tcl_Obj *) * objc);
+	} else {
+	    props->readable.list = (Tcl_Obj **)ckalloc(sizeof(Tcl_Obj *) * objc);
+	}
+    }
+    props->readable.num = 0;
+    if (objc > 0) {
+	Tcl_InitObjHashTable(&uniqueTable);
+	for (i=n=0 ; i<objc ; i++) {
+	    Tcl_CreateHashEntry(&uniqueTable, objv[i], &created);
+	    if (created) {
+		props->readable.list[n++] = objv[i];
+	    } else {
+		Tcl_DecrRefCount(objv[i]);
+	    }
+	}
+	props->readable.num = n;
+
+	/*
+	 * Shouldn't be necessary, but maintain num/list invariant.
+	 */
+
+	if (n != objc) {
+	    props->readable.list = (Tcl_Obj **)ckrealloc(props->readable.list,
+		    sizeof(Tcl_Obj *) * n);
+	}
+	Tcl_DeleteHashTable(&uniqueTable);
+    }
+}
+
+static int
+ClassRPropsGet(
+    TCL_UNUSED(void *),
+    Tcl_Interp *interp,
+    Tcl_ObjectContext context,
+    int objc,
+    Tcl_Obj *const *objv)
+{
+    Object *oPtr = (Object *) TclOOGetDefineCmdContext(interp);
+    Tcl_Obj *resultObj, *propNameObj;
+    int i;
+
+    if (Tcl_ObjectContextSkippedArgs(context) != objc) {
+	Tcl_WrongNumArgs(interp, Tcl_ObjectContextSkippedArgs(context), objv,
+		NULL);
+	return TCL_ERROR;
+    }
+    if (oPtr == NULL) {
+	return TCL_ERROR;
+    } else if (!oPtr->classPtr) {
+	Tcl_SetObjResult(interp, Tcl_NewStringObj(
+		"attempt to misuse API", -1));
+	Tcl_SetErrorCode(interp, "TCL", "OO", "MONKEY_BUSINESS", NULL);
+	return TCL_ERROR;
+    }
+
+    resultObj = Tcl_NewObj();
+    FOREACH(propNameObj, oPtr->classPtr->properties.readable) {
+	Tcl_ListObjAppendElement(NULL, resultObj, propNameObj);
+    }
+    Tcl_SetObjResult(interp, resultObj);
+    return TCL_OK;
+}
+
+static int
+ClassRPropsSet(
+    TCL_UNUSED(void *),
+    Tcl_Interp *interp,
+    Tcl_ObjectContext context,
+    int objc,
+    Tcl_Obj *const *objv)
+{
+    Object *oPtr = (Object *) TclOOGetDefineCmdContext(interp);
+    int varc;
+    Tcl_Obj **varv;
+
+    if (Tcl_ObjectContextSkippedArgs(context) + 1 != objc) {
+	Tcl_WrongNumArgs(interp, Tcl_ObjectContextSkippedArgs(context), objv,
+		"filterList");
+	return TCL_ERROR;
+    }
+    objv += Tcl_ObjectContextSkippedArgs(context);
+
+    if (oPtr == NULL) {
+	return TCL_ERROR;
+    } else if (!oPtr->classPtr) {
+	Tcl_SetObjResult(interp, Tcl_NewStringObj(
+		"attempt to misuse API", -1));
+	Tcl_SetErrorCode(interp, "TCL", "OO", "MONKEY_BUSINESS", NULL);
+	return TCL_ERROR;
+    } else if (Tcl_ListObjGetElements(interp, objv[0], &varc,
+	    &varv) != TCL_OK) {
+	return TCL_ERROR;
+    }
+
+    InstallReadableProps(&oPtr->classPtr->properties, varc, varv);
+    BumpGlobalEpoch(interp, oPtr->classPtr);
+    return TCL_OK;
+}
+
+static int
+ObjRPropsGet(
+    TCL_UNUSED(void *),
+    Tcl_Interp *interp,
+    Tcl_ObjectContext context,
+    int objc,
+    Tcl_Obj *const *objv)
+{
+    Object *oPtr = (Object *) TclOOGetDefineCmdContext(interp);
+    Tcl_Obj *resultObj, *propNameObj;
+    int i;
+
+    if (Tcl_ObjectContextSkippedArgs(context) != objc) {
+	Tcl_WrongNumArgs(interp, Tcl_ObjectContextSkippedArgs(context), objv,
+		NULL);
+	return TCL_ERROR;
+    }
+    if (oPtr == NULL) {
+	return TCL_ERROR;
+    }
+
+    resultObj = Tcl_NewObj();
+    FOREACH(propNameObj, oPtr->properties.readable) {
+	Tcl_ListObjAppendElement(NULL, resultObj, propNameObj);
+    }
+    Tcl_SetObjResult(interp, resultObj);
+    return TCL_OK;
+}
+
+static int
+ObjRPropsSet(
+    TCL_UNUSED(void *),
+    Tcl_Interp *interp,
+    Tcl_ObjectContext context,
+    int objc,
+    Tcl_Obj *const *objv)
+{
+    Object *oPtr = (Object *) TclOOGetDefineCmdContext(interp);
+    int varc;
+    Tcl_Obj **varv;
+
+    if (Tcl_ObjectContextSkippedArgs(context) + 1 != objc) {
+	Tcl_WrongNumArgs(interp, Tcl_ObjectContextSkippedArgs(context), objv,
+		"filterList");
+	return TCL_ERROR;
+    }
+    objv += Tcl_ObjectContextSkippedArgs(context);
+
+    if (oPtr == NULL) {
+	return TCL_ERROR;
+    } else if (Tcl_ListObjGetElements(interp, objv[0], &varc,
+	    &varv) != TCL_OK) {
+	return TCL_ERROR;
+    }
+
+    InstallReadableProps(&oPtr->properties, varc, varv);
+    return TCL_OK;
+}
+
+/*
+ * ----------------------------------------------------------------------
+ *
+ * ClassWPropsGet, ClassWPropsSet, ObjWPropsGet, ObjWPropsSet --
+ *
+ *	Implementations of the "writableproperties" slot accessors for classes
+ *	and instances.
+ *
+ * ----------------------------------------------------------------------
+ */
+
+static void
+InstallWritableProps(
+    PropertyStorage *props,
+    int objc,
+    Tcl_Obj *const objv[])
+{
+    Tcl_Obj *propObj;
+    int i, n, created;
+    Tcl_HashTable uniqueTable;
+
+    if (props->allWritableCache) {
+	Tcl_DecrRefCount(props->allWritableCache);
+	props->allWritableCache = NULL;
+    }
+
+    for (i=0 ; i<objc ; i++) {
+	Tcl_IncrRefCount(objv[i]);
+    }
+    FOREACH(propObj, props->writable) {
+	Tcl_DecrRefCount(propObj);
+    }
+    if (i != objc) {
+	if (objc == 0) {
+	    ckfree(props->writable.list);
+	} else if (i) {
+	    props->writable.list = (Tcl_Obj **)ckrealloc(props->writable.list,
+		    sizeof(Tcl_Obj *) * objc);
+	} else {
+	    props->writable.list = (Tcl_Obj **)ckalloc(sizeof(Tcl_Obj *) * objc);
+	}
+    }
+    props->writable.num = 0;
+    if (objc > 0) {
+	Tcl_InitObjHashTable(&uniqueTable);
+	for (i=n=0 ; i<objc ; i++) {
+	    Tcl_CreateHashEntry(&uniqueTable, objv[i], &created);
+	    if (created) {
+		props->writable.list[n++] = objv[i];
+	    } else {
+		Tcl_DecrRefCount(objv[i]);
+	    }
+	}
+	props->writable.num = n;
+
+	/*
+	 * Shouldn't be necessary, but maintain num/list invariant.
+	 */
+
+	if (n != objc) {
+	    props->writable.list = (Tcl_Obj **)ckrealloc(props->writable.list,
+		    sizeof(Tcl_Obj *) * n);
+	}
+	Tcl_DeleteHashTable(&uniqueTable);
+    }
+}
+
+static int
+ClassWPropsGet(
+    TCL_UNUSED(void *),
+    Tcl_Interp *interp,
+    Tcl_ObjectContext context,
+    int objc,
+    Tcl_Obj *const *objv)
+{
+    Object *oPtr = (Object *) TclOOGetDefineCmdContext(interp);
+    Tcl_Obj *resultObj, *propNameObj;
+    int i;
+
+    if (Tcl_ObjectContextSkippedArgs(context) != objc) {
+	Tcl_WrongNumArgs(interp, Tcl_ObjectContextSkippedArgs(context), objv,
+		NULL);
+	return TCL_ERROR;
+    }
+    if (oPtr == NULL) {
+	return TCL_ERROR;
+    } else if (!oPtr->classPtr) {
+	Tcl_SetObjResult(interp, Tcl_NewStringObj(
+		"attempt to misuse API", -1));
+	Tcl_SetErrorCode(interp, "TCL", "OO", "MONKEY_BUSINESS", NULL);
+	return TCL_ERROR;
+    }
+
+    resultObj = Tcl_NewObj();
+    FOREACH(propNameObj, oPtr->classPtr->properties.writable) {
+	Tcl_ListObjAppendElement(NULL, resultObj, propNameObj);
+    }
+    Tcl_SetObjResult(interp, resultObj);
+    return TCL_OK;
+}
+
+static int
+ClassWPropsSet(
+    TCL_UNUSED(void *),
+    Tcl_Interp *interp,
+    Tcl_ObjectContext context,
+    int objc,
+    Tcl_Obj *const *objv)
+{
+    Object *oPtr = (Object *) TclOOGetDefineCmdContext(interp);
+    int varc;
+    Tcl_Obj **varv;
+
+    if (Tcl_ObjectContextSkippedArgs(context) + 1 != objc) {
+	Tcl_WrongNumArgs(interp, Tcl_ObjectContextSkippedArgs(context), objv,
+		"propertyList");
+	return TCL_ERROR;
+    }
+    objv += Tcl_ObjectContextSkippedArgs(context);
+
+    if (oPtr == NULL) {
+	return TCL_ERROR;
+    } else if (!oPtr->classPtr) {
+	Tcl_SetObjResult(interp, Tcl_NewStringObj(
+		"attempt to misuse API", -1));
+	Tcl_SetErrorCode(interp, "TCL", "OO", "MONKEY_BUSINESS", NULL);
+	return TCL_ERROR;
+    } else if (Tcl_ListObjGetElements(interp, objv[0], &varc,
+	    &varv) != TCL_OK) {
+	return TCL_ERROR;
+    }
+
+    InstallWritableProps(&oPtr->classPtr->properties, varc, varv);
+    BumpGlobalEpoch(interp, oPtr->classPtr);
+    return TCL_OK;
+}
+
+static int
+ObjWPropsGet(
+    TCL_UNUSED(void *),
+    Tcl_Interp *interp,
+    Tcl_ObjectContext context,
+    int objc,
+    Tcl_Obj *const *objv)
+{
+    Object *oPtr = (Object *) TclOOGetDefineCmdContext(interp);
+    Tcl_Obj *resultObj, *propNameObj;
+    int i;
+
+    if (Tcl_ObjectContextSkippedArgs(context) != objc) {
+	Tcl_WrongNumArgs(interp, Tcl_ObjectContextSkippedArgs(context), objv,
+		NULL);
+	return TCL_ERROR;
+    }
+    if (oPtr == NULL) {
+	return TCL_ERROR;
+    }
+
+    resultObj = Tcl_NewObj();
+    FOREACH(propNameObj, oPtr->properties.writable) {
+	Tcl_ListObjAppendElement(NULL, resultObj, propNameObj);
+    }
+    Tcl_SetObjResult(interp, resultObj);
+    return TCL_OK;
+}
+
+static int
+ObjWPropsSet(
+    TCL_UNUSED(void *),
+    Tcl_Interp *interp,
+    Tcl_ObjectContext context,
+    int objc,
+    Tcl_Obj *const *objv)
+{
+    Object *oPtr = (Object *) TclOOGetDefineCmdContext(interp);
+    int varc;
+    Tcl_Obj **varv;
+
+    if (Tcl_ObjectContextSkippedArgs(context) + 1 != objc) {
+	Tcl_WrongNumArgs(interp, Tcl_ObjectContextSkippedArgs(context), objv,
+		"propertyList");
+	return TCL_ERROR;
+    }
+    objv += Tcl_ObjectContextSkippedArgs(context);
+
+    if (oPtr == NULL) {
+	return TCL_ERROR;
+    } else if (Tcl_ListObjGetElements(interp, objv[0], &varc,
+	    &varv) != TCL_OK) {
+	return TCL_ERROR;
+    }
+
+    InstallWritableProps(&oPtr->properties, varc, varv);
+    return TCL_OK;
+}
+
+/*
  * Local Variables:
  * mode: c
  * c-basic-offset: 4
diff --git a/generic/tclOOInfo.c b/generic/tclOOInfo.c
index 1f27b41..bbaaf02 100644
--- a/generic/tclOOInfo.c
+++ b/generic/tclOOInfo.c
@@ -4,7 +4,7 @@
  *	This file contains the implementation of the ::oo-related [info]
  *	subcommands.
  *
- * Copyright © 2006-2011 Donal K. Fellows
+ * Copyright © 2006-2019 Donal K. Fellows
  *
  * See the file "license.terms" for information on usage and redistribution of
  * this file, and for a DISCLAIMER OF ALL WARRANTIES.
@@ -17,6 +17,7 @@
 #include "tclOOInt.h"
 
 static inline Class *	GetClassFromObj(Tcl_Interp *interp, Tcl_Obj *objPtr);
+static void		SortPropList(Tcl_Obj *list);
 static Tcl_ObjCmdProc InfoObjectCallCmd;
 static Tcl_ObjCmdProc InfoObjectClassCmd;
 static Tcl_ObjCmdProc InfoObjectDefnCmd;
@@ -28,6 +29,7 @@ static Tcl_ObjCmdProc InfoObjectMethodsCmd;
 static Tcl_ObjCmdProc InfoObjectMethodTypeCmd;
 static Tcl_ObjCmdProc InfoObjectMixinsCmd;
 static Tcl_ObjCmdProc InfoObjectNsCmd;
+static Tcl_ObjCmdProc InfoObjectPropCmd;
 static Tcl_ObjCmdProc InfoObjectVarsCmd;
 static Tcl_ObjCmdProc InfoObjectVariablesCmd;
 static Tcl_ObjCmdProc InfoClassCallCmd;
@@ -41,6 +43,7 @@ static Tcl_ObjCmdProc InfoClassInstancesCmd;
 static Tcl_ObjCmdProc InfoClassMethodsCmd;
 static Tcl_ObjCmdProc InfoClassMethodTypeCmd;
 static Tcl_ObjCmdProc InfoClassMixinsCmd;
+static Tcl_ObjCmdProc InfoClassPropCmd;
 static Tcl_ObjCmdProc InfoClassSubsCmd;
 static Tcl_ObjCmdProc InfoClassSupersCmd;
 static Tcl_ObjCmdProc InfoClassVariablesCmd;
@@ -61,6 +64,7 @@ static const EnsembleImplMap infoObjectCmds[] = {
     {"methodtype", InfoObjectMethodTypeCmd, TclCompileBasic2ArgCmd, NULL, NULL, 0},
     {"mixins",	   InfoObjectMixinsCmd,	    TclCompileBasic1ArgCmd, NULL, NULL, 0},
     {"namespace",  InfoObjectNsCmd,	    TclCompileInfoObjectNamespaceCmd, NULL, NULL, 0},
+    {"properties", InfoObjectPropCmd,	    TclCompileBasicMin1ArgCmd, NULL, NULL, 0},
     {"variables",  InfoObjectVariablesCmd,  TclCompileBasic1Or2ArgCmd, NULL, NULL, 0},
     {"vars",	   InfoObjectVarsCmd,	    TclCompileBasic1Or2ArgCmd, NULL, NULL, 0},
     {NULL, NULL, NULL, NULL, NULL, 0}
@@ -82,6 +86,7 @@ static const EnsembleImplMap infoClassCmds[] = {
     {"methods",	     InfoClassMethodsCmd,	TclCompileBasicMin1ArgCmd, NULL, NULL, 0},
     {"methodtype",   InfoClassMethodTypeCmd,	TclCompileBasic2ArgCmd, NULL, NULL, 0},
     {"mixins",	     InfoClassMixinsCmd,	TclCompileBasic1ArgCmd, NULL, NULL, 0},
+    {"properties",   InfoClassPropCmd,		TclCompileBasicMin1ArgCmd, NULL, NULL, 0},
     {"subclasses",   InfoClassSubsCmd,		TclCompileBasic1Or2ArgCmd, NULL, NULL, 0},
     {"superclasses", InfoClassSupersCmd,	TclCompileBasic1ArgCmd, NULL, NULL, 0},
     {"variables",    InfoClassVariablesCmd,	TclCompileBasic1Or2ArgCmd, NULL, NULL, 0},
@@ -1717,6 +1722,184 @@ InfoClassCallCmd(
 }
 
 /*
+ * ----------------------------------------------------------------------
+ *
+ * InfoClassPropCmd, InfoObjectPropCmd --
+ *
+ *	Implements [info class properties $clsName ?$option...?] and
+ *	[info object properties $objName ?$option...?]
+ *
+ * ----------------------------------------------------------------------
+ */
+
+enum PropOpt {
+    PROP_ALL, PROP_READABLE, PROP_WRITABLE
+};
+static const char *const propOptNames[] = {
+    "-all", "-readable", "-writable",
+    NULL
+};
+
+static int
+InfoClassPropCmd(
+    TCL_UNUSED(void *),
+    Tcl_Interp *interp,
+    int objc,
+    Tcl_Obj *const objv[])
+{
+    Class *clsPtr;
+    int i, idx, all = 0, writable = 0, allocated = 0;
+    Tcl_Obj *result, *propObj;
+
+    if (objc < 2) {
+	Tcl_WrongNumArgs(interp, 1, objv, "className ?options...?");
+	return TCL_ERROR;
+    }
+    clsPtr = GetClassFromObj(interp, objv[1]);
+    if (clsPtr == NULL) {
+	return TCL_ERROR;
+    }
+    for (i = 2; i < objc; i++) {
+	if (Tcl_GetIndexFromObj(interp, objv[i], propOptNames, "option", 0,
+		&idx) != TCL_OK) {
+	    return TCL_ERROR;
+	}
+	switch (idx) {
+	case PROP_ALL:
+	    all = 1;
+	    break;
+	case PROP_READABLE:
+	    writable = 0;
+	    break;
+	case PROP_WRITABLE:
+	    writable = 1;
+	    break;
+	}
+    }
+
+    /*
+     * Get the properties.
+     */
+
+    if (all) {
+	result = TclOOGetAllClassProperties(clsPtr, writable, &allocated);
+	if (allocated) {
+	    SortPropList(result);
+	}
+    } else {
+	result = Tcl_NewObj();
+	if (writable) {
+	    FOREACH(propObj, clsPtr->properties.writable) {
+		Tcl_ListObjAppendElement(NULL, result, propObj);
+	    }
+	} else {
+	    FOREACH(propObj, clsPtr->properties.readable) {
+		Tcl_ListObjAppendElement(NULL, result, propObj);
+	    }
+	}
+	SortPropList(result);
+    }
+    Tcl_SetObjResult(interp, result);
+    return TCL_OK;
+}
+
+static int
+InfoObjectPropCmd(
+    TCL_UNUSED(void *),
+    Tcl_Interp *interp,
+    int objc,
+    Tcl_Obj *const objv[])
+{
+    Object *oPtr;
+    int i, idx, all = 0, writable = 0, allocated = 0;
+    Tcl_Obj *result, *propObj;
+
+    if (objc < 2) {
+	Tcl_WrongNumArgs(interp, 1, objv, "objName ?options...?");
+	return TCL_ERROR;
+    }
+    oPtr = (Object *) Tcl_GetObjectFromObj(interp, objv[1]);
+    if (oPtr == NULL) {
+	return TCL_ERROR;
+    }
+    for (i = 2; i < objc; i++) {
+	if (Tcl_GetIndexFromObj(interp, objv[i], propOptNames, "option", 0,
+		&idx) != TCL_OK) {
+	    return TCL_ERROR;
+	}
+	switch (idx) {
+	case PROP_ALL:
+	    all = 1;
+	    break;
+	case PROP_READABLE:
+	    writable = 0;
+	    break;
+	case PROP_WRITABLE:
+	    writable = 1;
+	    break;
+	}
+    }
+
+    /*
+     * Get the properties.
+     */
+
+    if (all) {
+	result = TclOOGetAllObjectProperties(oPtr, writable, &allocated);
+	if (allocated) {
+	    SortPropList(result);
+	}
+    } else {
+	result = Tcl_NewObj();
+	if (writable) {
+	    FOREACH(propObj, oPtr->properties.writable) {
+		Tcl_ListObjAppendElement(NULL, result, propObj);
+	    }
+	} else {
+	    FOREACH(propObj, oPtr->properties.readable) {
+		Tcl_ListObjAppendElement(NULL, result, propObj);
+	    }
+	}
+	SortPropList(result);
+    }
+    Tcl_SetObjResult(interp, result);
+    return TCL_OK;
+}
+
+/*
+ * ----------------------------------------------------------------------
+ *
+ * SortPropList --
+ *	Sort a list of names of properties. Simple support function. Assumes
+ *	that the list Tcl_Obj is unshared and doesn't have a string
+ *	representation.
+ *
+ * ----------------------------------------------------------------------
+ */
+
+static int
+PropNameCompare(
+    const void *a,
+    const void *b)
+{
+    Tcl_Obj *first = *(Tcl_Obj **) a;
+    Tcl_Obj *second = *(Tcl_Obj **) b;
+
+    return strcmp(Tcl_GetString(first), Tcl_GetString(second));
+}
+
+static void
+SortPropList(
+    Tcl_Obj *list)
+{
+    int ec;
+    Tcl_Obj **ev;
+
+    Tcl_ListObjGetElements(NULL, list, &ec, &ev);
+    qsort(ev, ec, sizeof(Tcl_Obj *), PropNameCompare);
+}
+
+/*
  * Local Variables:
  * mode: c
  * c-basic-offset: 4
diff --git a/generic/tclOOInt.h b/generic/tclOOInt.h
index 0e666e9..031b910 100644
--- a/generic/tclOOInt.h
+++ b/generic/tclOOInt.h
@@ -161,6 +161,26 @@ typedef LIST_STATIC(Tcl_Obj *) VariableNameList;
 typedef LIST_STATIC(PrivateVariableMapping) PrivateVariableList;
 
 /*
+ * This type is used in various places.
+ */
+
+typedef struct {
+    LIST_STATIC(Tcl_Obj *) readable;
+				/* The readable properties slot. */
+    LIST_STATIC(Tcl_Obj *) writable;
+				/* The writable properties slot. */
+    Tcl_Obj *allReadableCache;	/* The cache of all readable properties
+				 * exposed by this object or class (in its
+				 * stereotypical instancs). Contains a sorted
+				 * unique list if not NULL. */
+    Tcl_Obj *allWritableCache;	/* The cache of all writable properties
+				 * exposed by this object or class (in its
+				 * stereotypical instances). Contains a sorted
+				 * unique list if not NULL. */
+    int epoch;			/* The epoch that the caches are valid for. */
+} PropertyStorage;
+
+/*
  * Now, the definition of what an object actually is.
  */
 
@@ -182,8 +202,8 @@ typedef struct Object {
     LIST_STATIC(Tcl_Obj *) filters;
 				/* List of filter names. */
     struct Class *classPtr;	/* This is non-NULL for all classes, and NULL
-				 *  for everything else. It points to the class
-				 *  structure. */
+				 * for everything else. It points to the class
+				 * structure. */
     Tcl_Size refCount;		/* Number of strong references to this object.
 				 * Note that there may be many more weak
 				 * references; this mechanism exists to
@@ -211,12 +231,15 @@ typedef struct Object {
 				 * used inside methods. */
     Tcl_Command myclassCommand;	/* Reference to this object's class dispatcher
 				 * command. */
+    PropertyStorage properties;	/* Information relating to the lists of
+				 * properties that this object *claims* to
+				 * support. */
 } Object;
 
-#define OBJECT_DESTRUCTING	1	/* Indicates that an object is being or has
-								 *  been destroyed  */
-#define DESTRUCTOR_CALLED 2	/* Indicates that evaluation of destructor script for the
-							   object has began */
+#define OBJECT_DESTRUCTING 1	/* Indicates that an object is being or has
+				 *  been destroyed  */
+#define DESTRUCTOR_CALLED 2	/* Indicates that evaluation of destructor
+				 * script for the object has began */
 #define OO_UNUSED_4	4	/* No longer used.  */
 #define ROOT_OBJECT 0x1000	/* Flag to say that this object is the root of
 				 * the class hierarchy and should be treated
@@ -319,6 +342,9 @@ typedef struct Class {
 				 * namespace is defined but doesn't exist; we
 				 * also check at setting time but don't check
 				 * between times. */
+    PropertyStorage properties;	/* Information relating to the lists of
+				 * properties that this class *claims* to
+				 * support. */
 } Class;
 
 /*
@@ -521,6 +547,10 @@ MODULE_SCOPE void	TclOODeleteContext(CallContext *contextPtr);
 MODULE_SCOPE void	TclOODeleteDescendants(Tcl_Interp *interp,
 			    Object *oPtr);
 MODULE_SCOPE void	TclOODelMethodRef(Method *method);
+MODULE_SCOPE Tcl_Obj *	TclOOGetAllClassProperties(Class *clsPtr,
+			    int writable, int *allocated);
+MODULE_SCOPE Tcl_Obj *	TclOOGetAllObjectProperties(Object *oPtr,
+			    int writable, int *allocated);
 MODULE_SCOPE CallContext *TclOOGetCallContext(Object *oPtr,
 			    Tcl_Obj *methodNameObj, int flags,
 			    Object *contextObjPtr, Class *contextClsPtr,
diff --git a/generic/tclOOScript.h b/generic/tclOOScript.h
index f2e99b0..407e919 100644
--- a/generic/tclOOScript.h
+++ b/generic/tclOOScript.h
@@ -29,7 +29,7 @@ static const char *tclOOSetupScript =
 "::namespace eval ::oo {\n"
 "\t::namespace path {}\n"
 "\tnamespace eval Helpers {\n"
-"\t\t::namespace path {}\n"
+"\t\tnamespace path {}\n"
 "\t\tproc callback {method args} {\n"
 "\t\t\tlist [uplevel 1 {::namespace which my}] $method {*}$args\n"
 "\t\t}\n"
@@ -98,9 +98,9 @@ static const char *tclOOSetupScript =
 "\t\t\tif {![info object isa class $d]} {\n"
 "\t\t\t\tcontinue\n"
 "\t\t\t}\n"
-"\t\t\tdefine $delegate ::oo::define::superclass -append $d\n"
+"\t\t\tdefine $delegate ::oo::define::superclass -appendifnew $d\n"
 "\t\t}\n"
-"\t\tobjdefine $class ::oo::objdefine::mixin -append $delegate\n"
+"\t\tobjdefine $class ::oo::objdefine::mixin -appendifnew $delegate\n"
 "\t}\n"
 "\tproc UpdateClassDelegatesAfterClone {originObject targetObject} {\n"
 "\t\tset originDelegate [DelegateName $originObject]\n"
@@ -141,34 +141,44 @@ static const char *tclOOSetupScript =
 "\t\t::namespace delete tmp\n"
 "\t}\n"
 "\tdefine Slot {\n"
-"\t\tmethod Get {} {\n"
+"\t\tmethod Get -unexport {} {\n"
 "\t\t\treturn -code error -errorcode {TCLOO ABSTRACT_SLOT} \"unimplemented\"\n"
 "\t\t}\n"
-"\t\tmethod Set list {\n"
+"\t\tmethod Set -unexport list {\n"
 "\t\t\treturn -code error -errorcode {TCLOO ABSTRACT_SLOT} \"unimplemented\"\n"
 "\t\t}\n"
-"\t\tmethod Resolve list {\n"
+"\t\tmethod Resolve -unexport list {\n"
 "\t\t\treturn $list\n"
 "\t\t}\n"
-"\t\tmethod -set args {\n"
+"\t\tmethod -set -export args {\n"
 "\t\t\tset my [namespace which my]\n"
 "\t\t\tset args [lmap a $args {uplevel 1 [list $my Resolve $a]}]\n"
 "\t\t\ttailcall my Set $args\n"
 "\t\t}\n"
-"\t\tmethod -append args {\n"
+"\t\tmethod -append -export args {\n"
 "\t\t\tset my [namespace which my]\n"
 "\t\t\tset args [lmap a $args {uplevel 1 [list $my Resolve $a]}]\n"
 "\t\t\tset current [uplevel 1 [list $my Get]]\n"
 "\t\t\ttailcall my Set [list {*}$current {*}$args]\n"
 "\t\t}\n"
-"\t\tmethod -clear {} {tailcall my Set {}}\n"
-"\t\tmethod -prepend args {\n"
+"\t\tmethod -appendifnew -export args {\n"
+"\t\t\tset my [namespace which my]\n"
+"\t\t\tset current [uplevel 1 [list $my Get]]\n"
+"\t\t\tset args [lmap a $args {\n"
+"\t\t\t\tset a [uplevel 1 [list $my Resolve $a]]\n"
+"\t\t\t\tif {$a in $current} continue\n"
+"\t\t\t\tset a\n"
+"\t\t\t}]\n"
+"\t\t\ttailcall my Set [list {*}$current {*}$args]\n"
+"\t\t}\n"
+"\t\tmethod -clear -export {} {tailcall my Set {}}\n"
+"\t\tmethod -prepend -export args {\n"
 "\t\t\tset my [namespace which my]\n"
 "\t\t\tset args [lmap a $args {uplevel 1 [list $my Resolve $a]}]\n"
 "\t\t\tset current [uplevel 1 [list $my Get]]\n"
 "\t\t\ttailcall my Set [list {*}$args {*}$current]\n"
 "\t\t}\n"
-"\t\tmethod -remove args {\n"
+"\t\tmethod -remove -export args {\n"
 "\t\t\tset my [namespace which my]\n"
 "\t\t\tset args [lmap a $args {uplevel 1 [list $my Resolve $a]}]\n"
 "\t\t\tset current [uplevel 1 [list $my Get]]\n"
@@ -177,7 +187,7 @@ static const char *tclOOSetupScript =
 "\t\t\t}]\n"
 "\t\t}\n"
 "\t\tforward --default-operation my -append\n"
-"\t\tmethod unknown {args} {\n"
+"\t\tmethod unknown -unexport {args} {\n"
 "\t\t\tset def --default-operation\n"
 "\t\t\tif {[llength $args] == 0} {\n"
 "\t\t\t\ttailcall my $def\n"
@@ -186,13 +196,12 @@ static const char *tclOOSetupScript =
 "\t\t\t}\n"
 "\t\t\tnext {*}$args\n"
 "\t\t}\n"
-"\t\texport -set -append -clear -prepend -remove\n"
-"\t\tunexport unknown destroy\n"
+"\t\tunexport destroy\n"
 "\t}\n"
 "\tobjdefine define::superclass forward --default-operation my -set\n"
 "\tobjdefine define::mixin forward --default-operation my -set\n"
 "\tobjdefine objdefine::mixin forward --default-operation my -set\n"
-"\tdefine object method <cloned> {originObject} {\n"
+"\tdefine object method <cloned> -unexport {originObject} {\n"
 "\t\tforeach p [info procs [info object namespace $originObject]::*] {\n"
 "\t\t\tset args [info args $p]\n"
 "\t\t\tset idx -1\n"
@@ -219,7 +228,7 @@ static const char *tclOOSetupScript =
 "\t\t\t}\n"
 "\t\t}\n"
 "\t}\n"
-"\tdefine class method <cloned> {originObject} {\n"
+"\tdefine class method <cloned> -unexport {originObject} {\n"
 "\t\tnext $originObject\n"
 "\t\t::oo::UpdateClassDelegatesAfterClone $originObject [self]\n"
 "\t}\n"
@@ -235,7 +244,7 @@ static const char *tclOOSetupScript =
 "\t\t\t\t\t\t::return -code error -errorcode {TCLOO SINGLETON} \\\n"
 "\t\t\t\t\t\t\t\"may not destroy a singleton object\"\n"
 "\t\t\t\t\t}\n"
-"\t\t\t\t\tmethod <cloned> {originObject} {\n"
+"\t\t\t\t\tmethod <cloned> -unexport {originObject} {\n"
 "\t\t\t\t\t\t::return -code error -errorcode {TCLOO SINGLETON} \\\n"
 "\t\t\t\t\t\t\t\"may not clone a singleton object\"\n"
 "\t\t\t\t\t}\n"
@@ -248,6 +257,226 @@ static const char *tclOOSetupScript =
 "\t\tsuperclass class\n"
 "\t\tunexport create createWithNamespace new\n"
 "\t}\n"
+"\t::namespace eval configuresupport {\n"
+"\t\tnamespace path ::tcl\n"
+"\t\tproc PropertyImpl {readslot writeslot args} {\n"
+"\t\t\tfor {set i 0} {$i < [llength $args]} {incr i} {\n"
+"\t\t\t\tset prop [lindex $args $i]\n"
+"\t\t\t\tif {[string match \"-*\" $prop]} {\n"
+"\t\t\t\t\treturn -code error -level 2 \\\n"
+"\t\t\t\t\t\t-errorcode {TCLOO PROPERTY_FORMAT} \\\n"
+"\t\t\t\t\t\t\"bad property name \\\"$prop\\\": must not begin with -\"\n"
+"\t\t\t\t}\n"
+"\t\t\t\tif {$prop ne [list $prop]} {\n"
+"\t\t\t\t\treturn -code error -level 2 \\\n"
+"\t\t\t\t\t\t-errorcode {TCLOO PROPERTY_FORMAT} \\\n"
+"\t\t\t\t\t\t\"bad property name \\\"$prop\\\": must be a simple word\"\n"
+"\t\t\t\t}\n"
+"\t\t\t\tif {[string first \"::\" $prop] != -1} {\n"
+"\t\t\t\t\treturn -code error -level 2 \\\n"
+"\t\t\t\t\t\t-errorcode {TCLOO PROPERTY_FORMAT} \\\n"
+"\t\t\t\t\t\t\"bad property name \\\"$prop\\\": must not contain namespace separators\"\n"
+"\t\t\t\t}\n"
+"\t\t\t\tif {[string match {*[()]*} $prop]} {\n"
+"\t\t\t\t\treturn -code error -level 2 \\\n"
+"\t\t\t\t\t\t-errorcode {TCLOO PROPERTY_FORMAT} \\\n"
+"\t\t\t\t\t\t\"bad property name \\\"$prop\\\": must not contain parentheses\"\n"
+"\t\t\t\t}\n"
+"\t\t\t\tset realprop [string cat \"-\" $prop]\n"
+"\t\t\t\tset getter [format {::set [my varname %s]} $prop]\n"
+"\t\t\t\tset setter [format {::set [my varname %s] $value} $prop]\n"
+"\t\t\t\tset kind readwrite\n"
+"\t\t\t\twhile {[set next [lindex $args [expr {$i + 1}]]\n"
+"\t\t\t\t\t\tstring match \"-*\" $next]} {\n"
+"\t\t\t\t\tset arg [lindex $args [incr i 2]]\n"
+"\t\t\t\t\tswitch [prefix match -error [list -level 2 -errorcode \\\n"
+"\t\t\t\t\t\t\t[list TCL LOOKUP INDEX option $next]] {-get -kind -set} $next] {\n"
+"\t\t\t\t\t\t-get {\n"
+"\t\t\t\t\t\t\tif {$i >= [llength $args]} {\n"
+"\t\t\t\t\t\t\t\treturn -code error -level 2 \\\n"
+"\t\t\t\t\t\t\t\t\t-errorcode {TCL WRONGARGS} \\\n"
+"\t\t\t\t\t\t\t\t\t\"missing body to go with -get option\"\n"
+"\t\t\t\t\t\t\t}\n"
+"\t\t\t\t\t\t\tset getter $arg\n"
+"\t\t\t\t\t\t}\n"
+"\t\t\t\t\t\t-set {\n"
+"\t\t\t\t\t\t\tif {$i >= [llength $args]} {\n"
+"\t\t\t\t\t\t\t\treturn -code error -level 2 \\\n"
+"\t\t\t\t\t\t\t\t\t-errorcode {TCL WRONGARGS} \\\n"
+"\t\t\t\t\t\t\t\t\t\"missing body to go with -set option\"\n"
+"\t\t\t\t\t\t\t}\n"
+"\t\t\t\t\t\t\tset setter $arg\n"
+"\t\t\t\t\t\t}\n"
+"\t\t\t\t\t\t-kind {\n"
+"\t\t\t\t\t\t\tif {$i >= [llength $args]} {\n"
+"\t\t\t\t\t\t\t\treturn -code error -level 2\\\n"
+"\t\t\t\t\t\t\t\t\t-errorcode {TCL WRONGARGS} \\\n"
+"\t\t\t\t\t\t\t\t\t\"missing kind value to go with -kind option\"\n"
+"\t\t\t\t\t\t\t}\n"
+"\t\t\t\t\t\t\tset kind [prefix match -message \"kind\" -error [list \\\n"
+"\t\t\t\t\t\t\t\t\t-level 2 \\\n"
+"\t\t\t\t\t\t\t\t\t-errorcode [list TCL LOOKUP INDEX kind $arg]] {\n"
+"\t\t\t\t\t\t\t\treadable readwrite writable\n"
+"\t\t\t\t\t\t\t} $arg]\n"
+"\t\t\t\t\t\t}\n"
+"\t\t\t\t\t}\n"
+"\t\t\t\t}\n"
+"\t\t\t\tset reader <ReadProp$realprop>\n"
+"\t\t\t\tset writer <WriteProp$realprop>\n"
+"\t\t\t\tswitch $kind {\n"
+"\t\t\t\t\treadable {\n"
+"\t\t\t\t\t\tuplevel 2 [list $readslot -append $realprop]\n"
+"\t\t\t\t\t\tuplevel 2 [list $writeslot -remove $realprop]\n"
+"\t\t\t\t\t\tuplevel 2 [list method $reader -unexport {} $getter]\n"
+"\t\t\t\t\t}\n"
+"\t\t\t\t\twritable {\n"
+"\t\t\t\t\t\tuplevel 2 [list $readslot -remove $realprop]\n"
+"\t\t\t\t\t\tuplevel 2 [list $writeslot -append $realprop]\n"
+"\t\t\t\t\t\tuplevel 2 [list method $writer -unexport {value} $setter]\n"
+"\t\t\t\t\t}\n"
+"\t\t\t\t\treadwrite {\n"
+"\t\t\t\t\t\tuplevel 2 [list $readslot -append $realprop]\n"
+"\t\t\t\t\t\tuplevel 2 [list $writeslot -append $realprop]\n"
+"\t\t\t\t\t\tuplevel 2 [list method $reader -unexport {} $getter]\n"
+"\t\t\t\t\t\tuplevel 2 [list method $writer -unexport {value} $setter]\n"
+"\t\t\t\t\t}\n"
+"\t\t\t\t}\n"
+"\t\t\t}\n"
+"\t\t}\n"
+"\t\tnamespace eval configurableclass {\n"
+"\t\t\t::proc property args {\n"
+"\t\t\t\t::oo::configuresupport::PropertyImpl \\\n"
+"\t\t\t\t\t::oo::configuresupport::readableproperties \\\n"
+"\t\t\t\t\t::oo::configuresupport::writableproperties {*}$args\n"
+"\t\t\t}\n"
+"\t\t\t::proc properties args {::tailcall property {*}$args}\n"
+"\t\t\t::namespace path ::oo::define\n"
+"\t\t\t::namespace export property\n"
+"\t\t}\n"
+"\t\tnamespace eval configurableobject {\n"
+"\t\t\t::proc property args {\n"
+"\t\t\t\t::oo::configuresupport::PropertyImpl \\\n"
+"\t\t\t\t\t::oo::configuresupport::objreadableproperties \\\n"
+"\t\t\t\t\t::oo::configuresupport::objwritableproperties {*}$args\n"
+"\t\t\t}\n"
+"\t\t\t::proc properties args {::tailcall property {*}$args}\n"
+"\t\t\t::namespace path ::oo::objdefine\n"
+"\t\t\t::namespace export property\n"
+"\t\t}\n"
+"\t\tproc ReadAll {object my} {\n"
+"\t\t\tset result {}\n"
+"\t\t\tforeach prop [info object properties $object -all -readable] {\n"
+"\t\t\t\ttry {\n"
+"\t\t\t\t\tdict set result $prop [$my <ReadProp$prop>]\n"
+"\t\t\t\t} on error {msg opt} {\n"
+"\t\t\t\t\tdict set opt -level 2\n"
+"\t\t\t\t\treturn -options $opt $msg\n"
+"\t\t\t\t} on return {msg opt} {\n"
+"\t\t\t\t\tdict incr opt -level 2\n"
+"\t\t\t\t\treturn -options $opt $msg\n"
+"\t\t\t\t} on break {} {\n"
+"\t\t\t\t\treturn -code error -level 2 -errorcode {TCLOO SHENANIGANS} \\\n"
+"\t\t\t\t\t\t\"property getter for $prop did a break\"\n"
+"\t\t\t\t} on continue {} {\n"
+"\t\t\t\t\treturn -code error -level 2 -errorcode {TCLOO SHENANIGANS} \\\n"
+"\t\t\t\t\t\t\"property getter for $prop did a continue\"\n"
+"\t\t\t\t}\n"
+"\t\t\t}\n"
+"\t\t\treturn $result\n"
+"\t\t}\n"
+"\t\tproc ReadOne {object my propertyName} {\n"
+"\t\t\tset props [info object properties $object -all -readable]\n"
+"\t\t\ttry {\n"
+"\t\t\t\tset prop [prefix match -message \"property\" $props $propertyName]\n"
+"\t\t\t} on error {msg} {\n"
+"\t\t\t\tcatch {\n"
+"\t\t\t\t\tset wps [info object properties $object -all -writable]\n"
+"\t\t\t\t\tset wprop [prefix match $wps $propertyName]\n"
+"\t\t\t\t\tset msg \"property \\\"$wprop\\\" is write only\"\n"
+"\t\t\t\t}\n"
+"\t\t\t\treturn -code error -level 2 -errorcode [list \\\n"
+"\t\t\t\t\t\tTCL LOOKUP INDEX property $propertyName] $msg\n"
+"\t\t\t}\n"
+"\t\t\ttry {\n"
+"\t\t\t\tset value [$my <ReadProp$prop>]\n"
+"\t\t\t} on error {msg opt} {\n"
+"\t\t\t\tdict set opt -level 2\n"
+"\t\t\t\treturn -options $opt $msg\n"
+"\t\t\t} on return {msg opt} {\n"
+"\t\t\t\tdict incr opt -level 2\n"
+"\t\t\t\treturn -options $opt $msg\n"
+"\t\t\t} on break {} {\n"
+"\t\t\t\treturn -code error -level 2 -errorcode {TCLOO SHENANIGANS} \\\n"
+"\t\t\t\t\t\"property getter for $prop did a break\"\n"
+"\t\t\t} on continue {} {\n"
+"\t\t\t\treturn -code error -level 2 -errorcode {TCLOO SHENANIGANS} \\\n"
+"\t\t\t\t\t\"property getter for $prop did a continue\"\n"
+"\t\t\t}\n"
+"\t\t\treturn $value\n"
+"\t\t}\n"
+"\t\tproc WriteMany {object my setterMap} {\n"
+"\t\t\tset props [info object properties $object -all -writable]\n"
+"\t\t\tforeach {prop value} $setterMap {\n"
+"\t\t\t\ttry {\n"
+"\t\t\t\t\tset prop [prefix match -message \"property\" $props $prop]\n"
+"\t\t\t\t} on error {msg} {\n"
+"\t\t\t\t\tcatch {\n"
+"\t\t\t\t\t\tset rps [info object properties $object -all -readable]\n"
+"\t\t\t\t\t\tset rprop [prefix match $rps $prop]\n"
+"\t\t\t\t\t\tset msg \"property \\\"$rprop\\\" is read only\"\n"
+"\t\t\t\t\t}\n"
+"\t\t\t\t\treturn -code error -level 2 -errorcode [list \\\n"
+"\t\t\t\t\t\t\tTCL LOOKUP INDEX property $prop] $msg\n"
+"\t\t\t\t}\n"
+"\t\t\t\ttry {\n"
+"\t\t\t\t\t$my <WriteProp$prop> $value\n"
+"\t\t\t\t} on error {msg opt} {\n"
+"\t\t\t\t\tdict set opt -level 2\n"
+"\t\t\t\t\treturn -options $opt $msg\n"
+"\t\t\t\t} on return {msg opt} {\n"
+"\t\t\t\t\tdict incr opt -level 2\n"
+"\t\t\t\t\treturn -options $opt $msg\n"
+"\t\t\t\t} on break {} {\n"
+"\t\t\t\t\treturn -code error -level 2 -errorcode {TCLOO SHENANIGANS} \\\n"
+"\t\t\t\t\t\t\"property setter for $prop did a break\"\n"
+"\t\t\t\t} on continue {} {\n"
+"\t\t\t\t\treturn -code error -level 2 -errorcode {TCLOO SHENANIGANS} \\\n"
+"\t\t\t\t\t\t\"property setter for $prop did a continue\"\n"
+"\t\t\t\t}\n"
+"\t\t\t}\n"
+"\t\t\treturn\n"
+"\t\t}\n"
+"\t\t::oo::class create configurable {\n"
+"\t\t\tprivate variable my\n"
+"\t\t\tmethod configure -export args {\n"
+"\t\t\t\t::if {![::info exists my]} {\n"
+"\t\t\t\t\t::set my [::namespace which my]\n"
+"\t\t\t\t}\n"
+"\t\t\t\t::if {[::llength $args] == 0} {\n"
+"\t\t\t\t\t::oo::configuresupport::ReadAll [self] $my\n"
+"\t\t\t\t} elseif {[::llength $args] == 1} {\n"
+"\t\t\t\t\t::oo::configuresupport::ReadOne [self] $my \\\n"
+"\t\t\t\t\t\t[::lindex $args 0]\n"
+"\t\t\t\t} elseif {[::llength $args] % 2 == 0} {\n"
+"\t\t\t\t\t::oo::configuresupport::WriteMany [self] $my $args\n"
+"\t\t\t\t} else {\n"
+"\t\t\t\t\t::return -code error -errorcode {TCL WRONGARGS} \\\n"
+"\t\t\t\t\t\t[::format {wrong # args: should be \"%s\"} \\\n"
+"\t\t\t\t\t\t\t\"[self] configure \?-option value ...\?\"]\n"
+"\t\t\t\t}\n"
+"\t\t\t}\n"
+"\t\t\tdefinitionnamespace -instance configurableobject\n"
+"\t\t\tdefinitionnamespace -class configurableclass\n"
+"\t\t}\n"
+"\t}\n"
+"\tclass create configurable {\n"
+"\t\tsuperclass class\n"
+"\t\tconstructor {{definitionScript \"\"}} {\n"
+"\t\t\tnext {mixin ::oo::configuresupport::configurable}\n"
+"\t\t\tnext $definitionScript\n"
+"\t\t}\n"
+"\t\tdefinitionnamespace -class configuresupport::configurableclass\n"
+"\t}\n"
 "}\n"
 /* !END!: Do not edit above this line. */
 ;