Note: you have to create the anonymous reference -- you can't just push a value if the key doesn't exist.

In perl you can ;-) 

use strict;
use warnings;
use Data::Dumper;

my %hash;
push @{$hash{key}}, 'value';
print Dumper \%hash;
__END__
$VAR1 = {
          'key' => [
                     'value'
                   ]
        };

[download]

This nice feature is called "autovivification" and is quite useful most of the time.

In reply to Re^2: multiple values for one key in hash by moritz
in thread multiple values for one key in hash by sovixi

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