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Moose::Cookbook::Extending::Mooseish_MooseSugar - Acting like and providing sugar Moose-style


version 2.2207


  package MyApp::Mooseish;

  use Moose::Exporter;

      with_meta       => ['has_table'],
      class_metaroles => {
          class => ['MyApp::Meta::Class::Trait::HasTable'],

  sub has_table {
      my $meta = shift;

  package MyApp::Meta::Class::Trait::HasTable;
  use Moose::Role;

  has table => (
      is  => 'rw',
      isa => 'Str',


This recipe expands on the use of Moose::Exporter we saw in Moose::Cookbook::Extending::ExtensionOverview and the class metaclass trait we saw in Moose::Cookbook::Meta::Table_MetaclassTrait. In this example we provide our own metaclass trait, and we also export a has_table sugar function.

The with_meta parameter specifies a list of functions that should be wrapped before exporting. The wrapper simply ensures that the importing package's appropriate metaclass object is the first argument to the function, so we can do my $meta = 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 namespace::autoclean;

  use Moose;
  use MyApp::Mooseish;

  has_table 'User';

  has 'username' => ( is => 'ro' );
  has 'password' => ( is => 'ro' );

  sub login { ... }


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


  • Stevan Little <>

  • Dave Rolsky <>

  • Jesse Luehrs <>

  • Shawn M Moore <>

  • יובל קוג'מן (Yuval Kogman) <>

  • Karen Etheridge <>

  • Florian Ragwitz <>

  • Hans Dieter Pearcey <>

  • Chris Prather <>

  • Matt S Trout <>


This software is copyright (c) 2006 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.