The Signal Exception Condition routine generates a signal that
    indicates that an exception condition has occurred in your
    program. If a condition handler does not take corrective action
    and the condition is severe, then your program will exit.

    Format

      LIB$SIGNAL  condition-value [,condition-argument...]

                  [,condition-value-n [,condition-argument-n...]...]

  Additional Information (explode) :

• Returns
• Arguments