This function will check whether the current active Tcl interpreter
(CDM_Interp) holds the empty object as its value. In such a case, 1
(true) will be returned. If the interpreter does not has the empty
object as its value, 0 (false) will be returned.
Return Value:
This function will return 1 (true) if the current active Tcl
interpreter (CDM_Interp) has the empty ovject as its value, 0 (false)
otherwise. In case the current active Tcl interpreter (CDM_Interp) is
not a valid interpreter, 0 will be returned as well.