You can combine it into one hash. 
use Data::Dumper;

$hash{ABC}{desc} = "foo";
$hash{DEF}{desc} = "bar";
$hash{XYZ}{desc} = "baz";
$hash{YYY}{desc} = "quzz";

foreach $key (keys %hash){
    if ($hash{$key}{desc} =~ /^[foo|bar]+\z/) {
        $hash{$key}{group} = "CaseA"    ;
    }
    if ($hash{$key}{desc} =~ /^[baz|quzz]+\z/){
        $hash{$key}{group} = "CaseZ"    ;
    }
}

print Dumper(\%hash);

__output__

$VAR1 = {
          'ABC' => {
                     'group' => 'CaseA',
                     'desc' => 'foo'
                   },
          'DEF' => {
                     'group' => 'CaseA',
                     'desc' => 'bar'
                   },
          'XYZ' => {
                     'group' => 'CaseZ',
                     'desc' => 'baz'
                   },
          'YYY' => {
                     'group' => 'CaseZ',
                     'desc' => 'quzz'
                   }
        };

[download]
Cheers ^_^

In reply to Re: Re: How to group keys by hash value by donno20
in thread How to group keys by hash value by Anonymous Monk

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