length[$QMName]

When I first saw this expression and the others like it, I thought "No way that compiles! This guy's not even showing us the code he's using!" Lo and behold: 

c:\@Work\Perl\monks>perl -wMstrict -le
"our $Depth;
 $Depth = 'foo';
 ;;
 if (length[$Depth] != 0) { print 'THIS WORKS?!?'; }
 ;;
 if (length[] != 0) { print 'THIS WORKS TOO?!?!?'; }
"
THIS WORKS?!?
THIS WORKS TOO?!?!?

[download]
The trick, I now realize, is that  [ ... ] is the anonymous array constructor. The  [$Depth] and  [] expressions build anonymous arrays of one and zero elements, respectively, and return references to the arrays. The reference is then stringized and its length (always non-zero) taken and compared to zero. If having meaningful code doesn't help you with your issue, you have a very, very serious problem indeed.

Give a man a fish:  <%-{-{-{-<

In reply to Re^5: WHY DOESN'T THIS WORK -- THIS WORKS?!? by AnomalousMonk
in thread WHY DOESN'T THIS WORK by Anonymous Monk

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