For some reason one might need to know the type name of a Tcl object. The type name is stored in Tcl_Obj's typePtr->name. Below is the small C extension ''typeof'' to get the type name. 

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	// typeof
	// BSD License
	
	#include <tcl.h>
	
	#ifdef WIN32
	#ifdef typeof_EXPORTS
	#define typeof_EXPORT __declspec(dllexport)
	#else
	#define typeof_EXPORT __declspec(dllimport)
	#endif
	#else
	#define typeof_EXPORT 
	#endif
	
	static int Typeof_Cmd(ClientData clientData, Tcl_Interp *interp, int argc, Tcl_Obj *const argv[]);
	
	
	int typeof_EXPORT Typeof_Init(Tcl_Interp *interp)
	{
		/*
		* This may work with 8.0, but we are using strictly stubs here,
		* which requires 8.1.
		*/
		if (Tcl_InitStubs(interp, "8.1", 0) == NULL) {
			return TCL_ERROR;
		}
		if (Tcl_PkgRequire(interp, "Tcl", "8.1", 0) == NULL) {
			return TCL_ERROR;
		}
		if (Tcl_PkgProvide(interp, "typeof", "0.1.1") != TCL_OK) {
			return TCL_ERROR;
		}
	
		Tcl_CreateObjCommand(interp, "typeof", (Tcl_ObjCmdProc *) Typeof_Cmd, 
							(ClientData)NULL, (Tcl_CmdDeleteProc *)NULL);
	
		return TCL_OK;
	}
	
	static int Typeof_Cmd(ClientData clientData, Tcl_Interp *interp, int argc, Tcl_Obj *const argv[])
	{
	if (argc != 2)
	{
		Tcl_WrongNumArgs (interp, 1, argv, "object");
		return TCL_ERROR;
	}
	
	if(argv[1]->typePtr) {
		Tcl_SetObjResult (interp, Tcl_NewStringObj (argv[1]->typePtr->name, -1));
	} else {
		Tcl_SetObjResult (interp, Tcl_NewStringObj ("", -1));
	}
		return TCL_OK;
	}

----

'''Usage:'''
 typeof object

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%| Extensions |%
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