Collection::Utl::HashUnion -  Union hashes.

    use Collection::Utl::HashUnion;

   tie %hashu, 'Collection::Utl::HashUnion', \%hash1, \%hash2;

Handle collections key _changed

Tie::StdHash

Zahatski Aliaksandr, <zag@cpan.org>

Copyright (C) 2005-2008 by Zahatski Aliaksandr

This library is free software; you can redistribute it and/or modify it under the same terms as Perl itself, either Perl version 5.8.8 or, at your option, any later version of Perl 5 you may have available.