Identifies the top-most error on the error stack.
Tool_Err.Toperror CONSTANT PLS_INTEGER;
/*
** Print top-most error on the stack. The same
** results are produced by calling Tool_Err.Message
** with no arguments.
*/
BEGIN
. . .
TEXT_IO.PUT_LINE(TOOL_ERR.MESSAGE(TOOL_ERR.TOPERROR));
. . .
END;