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MooseX::Traits.3pm

NAME

MooseX::Traits - automatically apply roles at object creation time

SYNOPSIS

Given some roles:

   package Role;
   use Moose::Role;
   has foo => ( is => 'ro', isa => 'Int' required => 1 );
 
 

And a class:

   package Class;
   use Moose;
   with 'MooseX::Traits';
 
 

Apply the roles to the class at "new" time:

   my $class = Class->with_traits('Role')->new( foo => 42 );
 
 

Then use your customized class:

   $class->isa('Class'); # true
   $class->does('Role'); # true
   $class->foo; # 42
 
 

DESCRIPTION

Often you want to create components that can be added to a class arbitrarily. This module makes it easy for the end user to use these components. Instead of requiring the user to create a named class with the desired roles applied, or apply roles to the instance one-by-one, he can just create a new class from yours with "with_traits", and then instantiate that.

There is also "new_with_traits", which exists for compatibility reasons. It accepts a "traits" parameter, creates a new class with those traits, and then insantiates it.

    Class->new_with_traits( traits => [qw/Foo Bar/], foo => 42, bar => 1 )
 
 

returns exactly the same object as

    Class->with_traits(qw/Foo Bar/)->new( foo => 42, bar => 1 )
 
 

would. But you can also store the result of "with_traits", and call other methods:

    my $c = Class->with_traits(qw/Foo Bar/);
    $c->new( foo => 42 );
    $c->whatever( foo => 1234 );
 
 

And so on.

METHODS

$class->with_traits( @traits )

Return a new class with the traits applied. Use like:

$class->new_with_traits(%args, traits => \@traits)

"new_with_traits" can also take a hashref, e.g.:

   my $instance = $class->new_with_traits({ traits => \@traits, foo => 'bar' });
 
 

ATTRIBUTES YOUR CLASS GETS

This role will add the following attributes to the consuming class.

_trait_namespace

You can override the value of this attribute with "default" to automatically prepend a namespace to the supplied traits. (This can be overridden by prefixing the trait name with "+".)

Example:

   package Another::Trait;
   use Moose::Role;
   has 'bar' => (
       is       => 'ro',
       isa      => 'Str',
       required => 1,
   );
 
   package Another::Class;
   use Moose;
   with 'MooseX::Traits';
   has '+_trait_namespace' => ( default => 'Another' );
 
   my $instance = Another::Class->new_with_traits(
       traits => ['Trait'], # "Another::Trait", not "Trait"
       bar    => 'bar',
   );
   $instance->does('Trait')          # false
   $instance->does('Another::Trait') # true
 
   my $instance2 = Another::Class->new_with_traits(
       traits => ['+Trait'], # "Trait", not "Another::Trait"
   );
   $instance2->does('Trait')          # true
   $instance2->does('Another::Trait') # false
 
 

AUTHORS and CONTRIBUTORS

Jonathan Rockway "<jrockway@cpan.org>"

Stevan Little "<stevan.little@iinteractive.com>"

Tomas Doran "<bobtfish@bobtfish.net>"

Matt S. Trout "<mst@shadowcatsystems.co.uk>"

Jesse Luehrs "<doy at tozt dot net>"

Shawn Moore "<sartak@bestpractical.com>"

Florian Ragwitz "<rafl@debian.org>"

Chris Prather "<chris@prather.org>"

Yuval Kogman "<nothingmuch@woobling.org>"

COPYRIGHT AND LICENSE

Copyright 2008 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.