INSTALL :

% perl Makefile.PL
% make
% make test
% make install

DESCRIPTION :

This module lets you layer hashes on top of each other
opaquely so that top most layers obscure bottom ones.

Think of it like sheets of OHP transparencies, if a 
value is set in a top and bottom layer then that's 
you when you access that key you get the value from
the top layer but if you access something not set in
the top layer but set in the bottom layer then you
get the value from the bottom layer ...

... and breath.

In short :

Tied Hash :   foo=>'bob'  , quux=>'fleeg'
                 |              |     
                 ^              |
Layer 1   :   foo=>'bob'        ^
Layer 2   :   foo=>'bar'  , quux=>'fleeg'



So why is this useful. Well, the obvious application
is for preferences. In a CGI app you could tie in the 
bottom most hash to a database with default users' 
preferences, the second layer with the current user's 
preferences, the layer above that with the per 
session preferences and the layer above that with the 
per request values.

AUTHOR :

Simon Wistow <simon@twoshortplanks.com>

COPYING :

This module is distributed under the same terms as Perl itself
