/ 
Hash-Path-0.02
River stage one • 1 direct dependent • 2 total dependents
++
 / Hash::Path
Igor Sutton
and 1 contributors

NAME

Hash::Path - A simple way to return a path of HoH

VERSION

0.02

SYNOPSIS

         use Hash::Path;

         my $hash_ref = {
             key1 => {
                 key2 => {
                     key3 => 'value',
                 },
             },
         };

         my $wanted = Hash::Path->( $hash_ref, qw{key1 key2 key3} );

         # $wanted contains 'value'

DESCRIPTION

This module was written as proof of concept about how to find data inside a hash of hashes (HoH) with unknown structure. You can think that as hierarchical data like LDAP does, so our path could be the exactly the same as LDAP's dn, but a bit simpler because we (at least at this moment, who knows) don't want to deal with that.

This is a perfect companion for traversing YAML:

        use Hash::Path;
        use YAML;

        my ($hash_ref) = Load(<<'EOF');
        ---
        name: john
        permissions:
          some-module:
            - read
            - write
            - execute
          another-module:
            - read
        EOF
        my $permissions = Hash::Path->get($hash_ref, qw(permissions some-module));

        # $permissions contains [ 'read', 'write', 'execute' ]

API

get
        $scalar = Hash::Path->get($hash_ref, @path);

This is the only available method. It traverses the hash reference using the supplied path array, returning the value as scalar value.

hash_path
        use Hash::Path qw(hash_path);
        $scalar = hash_path($hash_ref, @path);

Now you can export the hash_path function to be a bit shorter. The parameters it takes are the same as get.

ACKNOWLEDGEMENTS

Thanks to Arthur Axel "fREW" Schmidt "<FREW@cpan.org>" for using this module and suggesting a better implementation for the get() method.

AUTHOR

Copyright (c) 2007, Igor Sutton Lopes "<IZUT@cpan.org>". All rights reserved.

This module is free software; you can redistribute it and/or modify it under the same terms as Perl itself.