NAME

Moose::Cookbook::Snack::Keywords - Restricted "keywords" in Moose

VERSION

version 1.9901

DESCRIPTION

Moose exports a number of sugar functions in order to emulate Perl built-in keywords. These can cause clashes with other user-defined functions. This document provides a list of those keywords for easy reference.

The 'meta' keyword

While most collisions can be avoided, you cannot avoid importing a meta method when you use Moose. If you try to override or change what meta does, you could end up breaking Moose internals.

Moose Keywords

If you are using Moose or Moose::Role its best to avoid these keywords:

extends

with

has

before

after

around

super

override

inner

augment

confess

blessed

Moose::Util::TypeConstraints Keywords

If you are using Moose::Util::TypeConstraints its best to avoid these keywords

type

subtype

class_type

role_type

maybe_type

as

where

message

optimize_as

coerce

from

via

enum

find_type_constraint

register_type_constraint

Avoiding collisions

Turning off Moose

To remove the sugar functions Moose exports just add no Moose at the bottom of your code:

            

              
              
package Thing;
use Moose;
# code here
no Moose;
            
          

This will unexport the sugar functions that Moose originally exported. The same will also work for Moose::Role and Moose::Util::TypeConstraints.

Sub::Exporter features

Moose, Moose::Role and Moose::Util::TypeConstraints all use Sub::Exporter to handle all their exporting needs. This means that all the features that Sub::Exporter provides are also available to them.

For instance, with Sub::Exporter you can rename keywords, like so:

            

              
              
package LOL::Cat;
use Moose 'has' => { -as => 'i_can_haz' };
i_can_haz 'cheeseburger' => (
    is      => 'rw',
    trigger => sub { print "NOM NOM" }
);
LOL::Cat->new->cheeseburger('KTHNXBYE');
            
          

See the Sub::Exporter docs for more information.

namespace::clean

You can also use namespace::clean to clean up your namespace, but you must be careful not to remove meta when doing so:

            

              
              
package Foo;
use Moose;
use namespace::clean -except => 'meta';
# ...
            
          

SEE ALSO

Moose

Moose::Role

Moose::Utils::TypeConstraints

Sub::Exporter

namespace::clean

AUTHOR

Stevan Little <stevan@iinteractive.com>

COPYRIGHT AND LICENSE

This software is copyright (c) 2010 by Infinity Interactive, Inc..

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

cpanm Moose

perl -MCPAN -e shell
install Moose