first = listLen;
    }

    if (last >= listLen) {
	last = listLen - 1;
    }
    if (first <= last) {
	numToDelete = last - first + 1;
	numToDelete = (unsigned)last - (unsigned)first + 1; /* See [3d3124d01d] */
    } else {
	numToDelete = 0;
    }

    /*
     * If the list object is unshared we can modify it directly, otherwise we
     * create a copy to modify: this is "copy on write".

	first = listLen;
    }

    if (last >= listLen) {
	last = listLen - 1;
    }
    if (first <= last) {
	numToDelete = last - first + 1;
	numToDelete = (unsigned)last - (unsigned)first + 1; /* See [3d3124d01d] */
    } else {
	numToDelete = 0;
    }

    if (Tcl_IsShared(listPtr)) {
	listPtr = TclListObjCopy(NULL, listPtr);
	createdNewObj = 1;

		TRACE_ERROR(interp);
		goto gotError;
	    }
	    if (toIdx > length) {
		toIdx = length;
	    }
	    if (toIdx >= fromIdx) {
		numToDelete = toIdx - fromIdx + 1;
		numToDelete = (unsigned)toIdx - (unsigned)fromIdx + 1; /* See [3d3124d01d] */
	    }
	}

	CACHE_STACK_INFO();

	if (Tcl_IsShared(valuePtr)) {
	    objResultPtr = Tcl_DuplicateObj(valuePtr);