Why is that not working? 
$ perl -MData::Dumper -e 'sub t{ $_+=1 for @_}; my %h = (1 => 2, 3 => 
+4); t(%h); print Dumper \%h'

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$VAR1 = {
          '1' => 3,
          '3' => 5
        };

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One could expect: 
$VAR1 = {
          '2' => 3,
          '4' => 5
        };

[download]

In reply to Modifying hash keys via aliasing by vsespb

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