I have a trivial project that has turned into something beyond my scope with recursive algorithms in perl. The following script does almost everything that I need, except print the full path to each value.

eaxmple:
3 => 6
should be
II/B/3 => 6

Please note that the final hash is unknown at runtime, and can be of any size and depth. The output format is specific to an old program that we still use, else I would just dump it using Data Dumper. 

#!/usr/bin/perl -w
use strict;

my %hash = (
        'I' => 1,
        'II' => {
        'A' => 3,
        'B' => {
            '1' => 4,
            '2' => 5,
            '3' => 6}
        },
        'III' => 2
        );


print_hash(\%hash);

sub print_hash {

    my($href) = @_;

    foreach my $key (keys %$href) {
    if (ref($$href{$key}) eq 'HASH') {
        my $href2 = $$href{$key};
        print_hash($href2);
    } 
    else {
        print "$key => $$href{$key}\n";
    }
    }
}

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In reply to Printing Hashes (Without Data Dumper) by Anonymous Monk

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