NOP

 ────NOP────;────────────────────────────────

NOP is a dummy instruction that has no effect. It can be useful as the target of a THEN or ELSE clause.

Example:

Select
   when a=b then nop           /* Do nothing */
   when a>b then say 'A > B'
   otherwise     say 'A < B'
end

┴╓: Using an extra semicolon instead of the NOP inserts a null clause, which is ignored. The second WHEN clause is seen as the first instruction expected after the THEN clause, and therefore is treated as a syntax error. NOP is a true instruction, however, and is a valid target for the THEN clause.

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