NAME

Hash::Dispatch - Find CODE in a hash (hashlike)

VERSION

version 0.0010

SYNOPSIS

$dispatch = Hash::Dispatch->dispatch(

    'xyzzy' => sub {
        return 'xyzzy';
    },

    qr/.../ => 'xyzzy',

    ...

);

$result = $dispatch->dispatch( 'xyzzy' );

$result->value->( ... );

DESCRIPTION

Hash::Dispatch is a tool for creating a hash-like lookup for returning a CODE reference

It is hash-like because a query against the dispatcher will only return once a CODE reference a found. If a key (a string or regular expression) maps to a string, then that will cause the lookup to begin again with the new value, recursing until a CODE reference is found or a deadend is reached:

a => CODE0
b => CODE1
c => CODE2
d => a
qr/z/ => c

query( a ) => CODE0
query( b ) => CODE1
query( d ) => CODE0
query( xyzzy ) => CODE2
query( j ) => undef

Hash::Dispatch will throw an exception if it is cycling:

a => b
b => a

query( a ) => {{{ Exception! }}}

USAGE

$dispatcher = Hash::Dispatch->dispatch( ... )

Returns a new $dispatcher with the given mapping

$result = $dispatcher->dispatch( <query> )

Search $dispatcher with <query>

Returns an object with a ->value method that contains the CODE reference

Returns undef is nothing is found

AUTHOR

Robert Krimen <robertkrimen@gmail.com>

COPYRIGHT AND LICENSE

This software is copyright (c) 2011 by Robert Krimen.

This is free software; you can redistribute it and/or modify it under the same terms as the Perl 5 programming language system itself.