2.4.11 The NOP Instruction NOP ; The NOP instruction is the “no operation” statement; it does nothing. Actually, that is not totally true, since the NOP instruction is a “real” statement (and a placeholder), as opposed to null clauses. I’ve only seen this used in two circumstances. · After any THEN or ELSE keyword, where a statement is required, when the programmer wants an empty THEN or ELSE part. By the way, this is the intended use of NOP. Note that you can not use a null clause there (label, comment, or empty lines), since these are not parsed as “independent” statements. · I have seen it used as “trace-bait”. That is, when you start interactive trace, the statement immediately after the TRACE instruction will be executed before you receive interactive control. If you don’t want that to happen (or maybe the TRACE instruction was the last in the program), you need to add an extra dummy statement. However, in this context, labels and comments can be used, too.
PREV NEXT