Moose::Cookbook::Extending::Recipe43pm

Usage

  package MyApp::Mooseish;
  use Moose ();
  use Moose::Exporter;
  Moose::Exporter->setup_import_methods(
      with_meta => ['has_table'],
      also      => 'Moose',
  );
  sub init_meta {
      shift;
      return Moose->init_meta( @_, metaclass => 'MyApp::Meta::Class' );
  }
  sub has_table {
      my $meta = shift;
      $meta->table(shift);
  }
  package MyApp::Meta::Class;
  use Moose;
  extends 'Moose::Meta::Class';
  has 'table' => ( is => 'rw' );

Overview

This recipe expands on the use of Moose::Exporter we saw in Moose::Cookbook::Extending::Recipe1. Instead of providing our own object base class, we provide our own metaclass class, and we also export a "has_table" sugar function.

Given the above code, you can now replace all instances of "use Moose" with "use MyApp::Mooseish". Similarly, "no Moose" is now replaced with "no MyApp::Mooseish".

The "with_meta" parameter specifies a list of functions that should be wrapped before exporting. The wrapper simply ensures that the importing package name is the first argument to the function, so we can do "my $caller = shift;".

See the Moose::Exporter docs for more details on its API.

USING MyApp::Mooseish

The purpose of all this code is to provide a Moose-like interface. Here's what it would look like in actual use:

  package MyApp::User;
  use MyApp::Mooseish;
  has_table 'User';
  has 'username' => ( is => 'ro' );
  has 'password' => ( is => 'ro' );
  sub login { ... }
  no MyApp::Mooseish;

All of the normal Moose sugar ("has()", "with()", etc) is available when you "use MyApp::Mooseish".

Conclusion

Providing sugar functions can make your extension look much more Moose-ish. See Fey::ORM for a more extensive example.

Copyright and license

Copyright 2006-2010 by Infinity Interactive, Inc.

<http://www.iinteractive.com>

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