I ran across this when trying to debug someone elses code earlier today and am just wondering what the general consensus of what this should do is.

use strict;
use Data::Dumper;
use CGI qw(:cgi);

my $r = CGI->new();

my %hash = (
            'key1' => 'value1',
            'key2' => $r->param('doesnt_exist'),
            'key3' => 'value3',
);

foreach my $key (keys %hash) {
    print "$key: $hash{$key}\n";
}

[download]
You end up with:
key1: value1
key2: key3
value3:

[download]

The param function inside of CGI.pm is returning on this statement:
return unless defined($name) && $self->{$name};
I was able to get rid of the problem by changing the call to param to:
$r->param('doesnt_exist') || undef
This keeps the has from being completely hosed.

My question is, what is wrong here... Is CGI.pm wrong, is the code wrong, is PERL wrong?

In reply to What should this do? by JackHammer

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