I sometimes find that, in the course of processing decisions, I write a construct similar to this ...

    ... doing something ...
    $tmp = "some result";  # not an actual value
    if($tmp eq 'F'){
        ;    # do nothing, spot held for clarity
    }elsif($tmp =~ /[MICL]/){
        ...  # do something ...
    }else{
        ...  # do something 
    }
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I know there are ways to eliminate the first comparison but I rather find the structure to be clearer. Still, I got to wondering about the NOOP code in the first if. Does Perl even have a NOOP code when it compiles? B::Deparse reported this construct as an empty list

        if ($tmp eq 'F') {
            ();
        }elsif ...
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OK, so is an empty list placed at this point in the bytecode so that when reached, the program evaluates the list? In what context? Or is this just a shorthand display for some NOOP code? Or am I missing some point entirely?

Thanks

Update: Thanks for the great information. Early in my Perl life, I benchmarked this construct a few times to satisfy myself that speed wasn't an issue. In all the instances that I tested, the construct using the NOOP was at least as fast as the original construct so I tend to opt for clarity.

I like the return if ... option although I still get twinges about having multiple exits from a subroutine. Just can't get that structured BASIC out of my soul ;o)

Thanks again.