* 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
 *
 * nsVarName - INTERNALREP DEFINITION:
 *   twoPtrValue.ptr1:	pointer to the namespace containing the reference
 *   twoPtrValue.ptr2:	pointer to the corresponding Var
 *
 * 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
 */