#!perl
use strict;
use warnings;
use Data::Dump::Streamer; 

my %dispatch = (
    original_a => sub {print "AAA\n"},
);

$dispatch{alias}=\&{$dispatch{original_a}};

print Dump(\%dispatch);

#OUTPUT
$HASH1 = {
           alias      => sub {
                           use warnings;
                           use strict 'refs';
                           print "AAA\n";
                         },
           original_a => 'V: $HASH1->{alias}'
         };
$HASH1->{original_a} = $HASH1->{alias};