Re: If hash not defined help

use strict; use warnings; 
use Data::Dumper; 
{
my $current= {
          'version' => '2.0',
          'xmlns:media' => 'http://search.yahoo.com/mrss/',
          'fileSet' => {
                       'time' => '1499387013',
                       'fileName' => 'Atlanta_Regency.gif',
                       'emailAddress' => 'johndoe@gmail.com',
                       'requesterName' => 'John Doe',
                       'showAbbreviation' => {},
                       'zoneColor' => '0'
                     }
        };

if (exists($current->{'fileSet'}->{'showAbbreviation'}) 
    && defined ($current->{'fileSet'}->{'showAbbreviation'}) 
    && ( scalar(keys %{$current->{'fileSet'}->{'showAbbreviation'}}) >
+0) 
    ) {
      my $showAbbreviation = $current->{'fileSet'}->{'showAbbreviation
+'};
      print "Yes: showAbbreviation\n";
      print Dumper($showAbbreviation)."\n";
    } else {
      print "No: showAbbreviation\n";
    }
}

{
my $current= {
          'version' => '2.0',
          'xmlns:media' => 'http://search.yahoo.com/mrss/',
          'fileSet' => {
                       'time' => '1499387013',
                       'fileName' => 'Atlanta_Regency.gif',
                       'emailAddress' => 'johndoe@gmail.com',
                       'requesterName' => 'John Doe',
                       'showAbbreviation' => {a=>1},
                       'zoneColor' => '0'
                     }
        };

if (exists($current->{'fileSet'}->{'showAbbreviation'}) 
    && defined ($current->{'fileSet'}->{'showAbbreviation'}) 
    && ( scalar(keys %{$current->{'fileSet'}->{'showAbbreviation'}}) >
+0) 
    ) {
      my $showAbbreviation = $current->{'fileSet'}->{'showAbbreviation
+'};
      print "Yes: showAbbreviation\n";
      print Dumper($showAbbreviation)."\n";
    } else {
      print "No: showAbbreviation\n";
    }
}
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Comment on Re: If hash not defined help Download Code

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Re^2: If hash not defined help by AnomalousMonk (Archbishop) on Jul 07, 2017 at 02:57 UTC
johnfl68: If `$current->{'fileSet'}{'showAbbreviation'}` could exist and be defined and yet be something other than a hash reference, it might be wise to add a test for hash-refitude to the other tests proposed by huck (attempting to dereference a non-hashref as a hash is fatal under strict refs, which you should, of course, have enabled :) (~~untested~~ \| since tested): `if (exists($current->{'fileSet'}->{'showAbbreviation'})` `&& defined ($current->{'fileSet'}->{'showAbbreviation'})` `&& 'HASH' eq ref($current->{'fileSet'}->{'showAbbreviation'})` `&& ( scalar(keys %{$current->{'fileSet'}->{'showAbbreviation'}}) >0)` `) {` `...` `}` Update: In fact, since ref returns the empty string for an undefined argument, the explicit defined test is not necessary, making the whole thing a bit less messy: `if (exists($current->{'fileSet'}->{'showAbbreviation'})` `&& 'HASH' eq ref($current->{'fileSet'}->{'showAbbreviation'})` `&& ( scalar(keys %{$current->{'fileSet'}->{'showAbbreviation'}}) >0)` `) {` `...` `}` Give a man a fish: `<%-{-{-{-<`	[reply] [d/l] [select]
Re^2: If hash not defined help by johnfl68 (Scribe) on Jul 07, 2017 at 04:50 UTC
Thank you. That helps now for when showAbbreviation is empty, but unfortunately if it has a value in it, for example 'Test', I get this error now... `Can't use string ("Test") as a HASH ref while "strict refs" in use.` I give up for tonight.	[reply] [d/l]
Re^3: If hash not defined help by AnomalousMonk (Archbishop) on Jul 07, 2017 at 05:39 UTC
`Can't use string ("Test") as a HASH ref ...` Maybe take a look at this. Give a man a fish: `<%-{-{-{-<`	[reply] [d/l] [select]