Monks ~

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;
}

[download]

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?

Thanks
--
man with no legs, inc.

In reply to Testing array of hash values by legLess

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