Based on (tye)Re: varying length multi-dimensional hashes: 

sub derefHashTree {
    my( $hv, @keys )= @_;
    my $ref= \$hv;
    for my $key (  @keys  ) {
        $ref= \$$ref->{$key};
    }
    return $$ref;
}

my %hash1;
$hash1{key1}{key2}{key3}{A} = "hello";
$hash1{key1}{key2}{key3}{B} = "bye";

my $new_hash = \%hash1;

my @keys= qw( key1 key2 key3 );

foreach(  keys %{ derefHashTree($new_hash,@keys) }  ) {
    print "$_\n";
}

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Note that you can return $ref; instead of $$ref if you want to modify the indicated value instead of just fetching it.

                - tye

In reply to Re: eval on hash (use \\) by tye
in thread eval on hash by Anonymous Monk

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