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Two questions here:

  1. Why doesn't this work like I expect ("false expectations" is my best answer, but it isn't helping me),
  2. Is there a better way to do what I'm attempting?

I want to format and display a heading iff that heading's children contain data.

#!/usr/bin/perl -T use strict; use warnings; # prints nothing, as expected print do_head( "Empty" ); # prints "<H4>Appearance</H4>"; wish it didn't my @p{ 'eyes', 'hair', 'etc' } = (); print do_head( "Appearance", @p{ 'eyes', 'hair', 'etc' }); #------------------------------------------------ sub do_head { my $heading = shift; my @data = @_; return "<H4>$heading</H4>" if @data; }

I expected the do_head sub to put an empty list into @data; said list would then evaluate as false in a scalar context. This doesn't work, of course, which is why I'm here. I'm sure this is based on my faulty understanding of arrays and hashes. I've re-read the Camel on this subject and not attained enlightenment. Help?

man with no legs, inc.

In reply to Testing array of hash values by legLess

Use:  <p> text here (a paragraph) </p>
and:  <code> code here </code>
to format your post; it's "PerlMonks-approved HTML":

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