-
package Moose::Role;
-
use strict;
use warnings;
use Scalar::Util 'blessed';
-use Carp 'confess';
-use Sub::Name 'subname';
+use Carp 'croak';
use Sub::Exporter;
-our $VERSION = '0.06';
+our $VERSION = '1.25';
+$VERSION = eval $VERSION;
+our $AUTHORITY = 'cpan:STEVAN';
-use Moose ();
+use Moose ();
+use Moose::Util ();
+use Moose::Exporter;
use Moose::Meta::Role;
use Moose::Util::TypeConstraints;
-{
- my ( $CALLER, %METAS );
-
- sub _find_meta {
- my $role = $CALLER;
-
- return $METAS{$role} if exists $METAS{$role};
-
- # make a subtype for each Moose class
- subtype $role
- => as 'Role'
- => where { $_->does($role) }
- => optimize_as { blessed($_[0]) && $_[0]->can('does') && $_[0]->does($role) }
- unless find_type_constraint($role);
-
- my $meta;
- if ($role->can('meta')) {
- $meta = $role->meta();
- (blessed($meta) && $meta->isa('Moose::Meta::Role'))
- || confess "You already have a &meta function, but it does not return a Moose::Meta::Role";
- }
- else {
- $meta = Moose::Meta::Role->initialize($role);
- $meta->Moose::Meta::Class::add_method('meta' => sub { $meta })
- }
-
- return $METAS{$role} = $meta;
+sub extends {
+ croak "Roles do not support 'extends' (you can use 'with' to specialize a role)";
+}
+
+sub with {
+ Moose::Util::apply_all_roles( shift, @_ );
+}
+
+sub requires {
+ my $meta = shift;
+ croak "Must specify at least one method" unless @_;
+ $meta->add_required_methods(@_);
+}
+
+sub excludes {
+ my $meta = shift;
+ croak "Must specify at least one role" unless @_;
+ $meta->add_excluded_roles(@_);
+}
+
+sub has {
+ my $meta = shift;
+ my $name = shift;
+ croak 'Usage: has \'name\' => ( key => value, ... )' if @_ == 1;
+ my %options = ( definition_context => Moose::Util::_caller_info(), @_ );
+ my $attrs = ( ref($name) eq 'ARRAY' ) ? $name : [ ($name) ];
+ $meta->add_attribute( $_, %options ) for @$attrs;
+}
+
+sub _add_method_modifier {
+ my $type = shift;
+ my $meta = shift;
+
+ if ( ref($_[0]) eq 'Regexp' ) {
+ croak "Roles do not currently support regex "
+ . " references for $type method modifiers";
}
-
-
- my %exports = (
- extends => sub {
- my $meta = _find_meta();
- return subname 'Moose::Role::extends' => sub {
- confess "Moose::Role does not currently support 'extends'"
- };
- },
- with => sub {
- my $meta = _find_meta();
- return subname 'Moose::Role::with' => sub (@) {
- my (@roles) = @_;
- confess "Must specify at least one role" unless @roles;
- Moose::_load_all_classes(@roles);
- ($_->can('meta') && $_->meta->isa('Moose::Meta::Role'))
- || confess "You can only consume roles, $_ is not a Moose role"
- foreach @roles;
- if (scalar @roles == 1) {
- $roles[0]->meta->apply($meta);
- }
- else {
- Moose::Meta::Role->combine(
- map { $_->meta } @roles
- )->apply($meta);
- }
- };
- },
- requires => sub {
- my $meta = _find_meta();
- return subname 'Moose::Role::requires' => sub (@) {
- confess "Must specify at least one method" unless @_;
- $meta->add_required_methods(@_);
- };
- },
- excludes => sub {
- my $meta = _find_meta();
- return subname 'Moose::Role::excludes' => sub (@) {
- confess "Must specify at least one role" unless @_;
- $meta->add_excluded_roles(@_);
- };
- },
- has => sub {
- my $meta = _find_meta();
- return subname 'Moose::Role::has' => sub ($;%) {
- my ($name, %options) = @_;
- $meta->add_attribute($name, %options)
- };
- },
- before => sub {
- my $meta = _find_meta();
- return subname 'Moose::Role::before' => sub (@&) {
- my $code = pop @_;
- $meta->add_before_method_modifier($_, $code) for @_;
- };
- },
- after => sub {
- my $meta = _find_meta();
- return subname 'Moose::Role::after' => sub (@&) {
- my $code = pop @_;
- $meta->add_after_method_modifier($_, $code) for @_;
- };
- },
- around => sub {
- my $meta = _find_meta();
- return subname 'Moose::Role::around' => sub (@&) {
- my $code = pop @_;
- $meta->add_around_method_modifier($_, $code) for @_;
- };
- },
- super => sub {
- my $meta = _find_meta();
- return subname 'Moose::Role::super' => sub {};
- },
- override => sub {
- my $meta = _find_meta();
- return subname 'Moose::Role::override' => sub ($&) {
- my ($name, $code) = @_;
- $meta->add_override_method_modifier($name, $code);
- };
- },
- inner => sub {
- my $meta = _find_meta();
- return subname 'Moose::Role::inner' => sub {
- confess "Moose::Role cannot support 'inner'";
- };
- },
- augment => sub {
- my $meta = _find_meta();
- return subname 'Moose::Role::augment' => sub {
- confess "Moose::Role cannot support 'augment'";
- };
- },
- confess => sub {
- return \&Carp::confess;
- },
- blessed => sub {
- return \&Scalar::Util::blessed;
- }
- );
-
- my $exporter = Sub::Exporter::build_exporter({
- exports => \%exports,
- groups => {
- default => [':all']
- }
- });
-
- sub import {
- $CALLER = caller();
-
- strict->import;
- warnings->import;
- # we should never export to main
- return if $CALLER eq 'main';
+ Moose::Util::add_method_modifier($meta, $type, \@_);
+}
+
+sub before { _add_method_modifier('before', @_) }
+
+sub after { _add_method_modifier('after', @_) }
- goto $exporter;
- };
+sub around { _add_method_modifier('around', @_) }
+# see Moose.pm for discussion
+sub super {
+ return unless $Moose::SUPER_BODY;
+ $Moose::SUPER_BODY->(@Moose::SUPER_ARGS);
+}
+
+sub override {
+ my $meta = shift;
+ my ( $name, $code ) = @_;
+ $meta->add_override_method_modifier( $name, $code );
+}
+
+sub inner {
+ croak "Roles cannot support 'inner'";
+}
+
+sub augment {
+ croak "Roles cannot support 'augment'";
+}
+
+Moose::Exporter->setup_import_methods(
+ with_meta => [
+ qw( with requires excludes has before after around override )
+ ],
+ as_is => [
+ qw( extends super inner augment ),
+ \&Carp::confess,
+ \&Scalar::Util::blessed,
+ ],
+);
+
+sub init_meta {
+ shift;
+ my %args = @_;
+
+ my $role = $args{for_class};
+
+ unless ($role) {
+ require Moose;
+ Moose->throw_error("Cannot call init_meta without specifying a for_class");
+ }
+
+ my $metaclass = $args{metaclass} || "Moose::Meta::Role";
+ my $meta_name = exists $args{meta_name} ? $args{meta_name} : 'meta';
+
+ Moose->throw_error("The Metaclass $metaclass must be a subclass of Moose::Meta::Role.")
+ unless $metaclass->isa('Moose::Meta::Role');
+
+ # make a subtype for each Moose role
+ role_type $role unless find_type_constraint($role);
+
+ my $meta;
+ if ( $meta = Class::MOP::get_metaclass_by_name($role) ) {
+ unless ( $meta->isa("Moose::Meta::Role") ) {
+ my $error_message = "$role already has a metaclass, but it does not inherit $metaclass ($meta).";
+ if ( $meta->isa('Moose::Meta::Class') ) {
+ Moose->throw_error($error_message . ' You cannot make the same thing a role and a class. Remove either Moose or Moose::Role.');
+ } else {
+ Moose->throw_error($error_message);
+ }
+ }
+ }
+ else {
+ $meta = $metaclass->initialize($role);
+ }
+
+ if (defined $meta_name) {
+ # also check for inherited non moose 'meta' method?
+ my $existing = $meta->get_method($meta_name);
+ if ($existing && !$existing->isa('Class::MOP::Method::Meta')) {
+ Carp::cluck "Moose::Role is overwriting an existing method named "
+ . "$meta_name in role $role with a method "
+ . "which returns the class's metaclass. If this is "
+ . "actually what you want, you should remove the "
+ . "existing method, otherwise, you should rename or "
+ . "disable this generated method using the "
+ . "'-meta_name' option to 'use Moose::Role'.";
+ }
+ $meta->_add_meta_method($meta_name);
+ }
+
+ return $meta;
}
1;
=head1 SYNOPSIS
package Eq;
- use strict;
- use warnings;
- use Moose::Role;
-
+ use Moose::Role; # automatically turns on strict and warnings
+
requires 'equal';
-
- sub no_equal {
+
+ sub no_equal {
my ($self, $other) = @_;
!$self->equal($other);
}
-
+
# ... then in your classes
-
+
package Currency;
- use strict;
- use warnings;
- use Moose;
-
+ use Moose; # automatically turns on strict and warnings
+
with 'Eq';
-
+
sub equal {
my ($self, $other) = @_;
$self->as_float == $other->as_float;
=head1 DESCRIPTION
-Role support in Moose is coming along quite well. It's best documentation
-is still the the test suite, but it is fairly safe to assume Perl 6 style
-behavior, and then either refer to the test suite, or ask questions on
-#moose if something doesn't quite do what you expect. More complete
-documentation is planned and will be included with the next official
-(non-developer) release.
+The concept of roles is documented in L<Moose::Manual::Roles>. This document
+serves as API documentation.
=head1 EXPORTED FUNCTIONS
-Currently Moose::Role supports all of the functions that L<Moose> exports,
-but differs slightly in how some items are handled (see L<CAVEATS> below
-for details).
+Moose::Role currently supports all of the functions that L<Moose> exports, but
+differs slightly in how some items are handled (see L</CAVEATS> below for
+details).
-Moose::Role also offers two role specific keyword exports:
+Moose::Role also offers two role-specific keyword exports:
=over 4
=item B<requires (@method_names)>
-Roles can require that certain methods are implemented by any class which
-C<does> the role.
+Roles can require that certain methods are implemented by any class which
+C<does> the role.
+
+Note that attribute accessors also count as methods for the purposes
+of satisfying the requirements of a role.
=item B<excludes (@role_names)>
Roles can C<exclude> other roles, in effect saying "I can never be combined
-with these C<@role_names>". This is a feature which should not be used
-lightly.
+with these C<@role_names>". This is a feature which should not be used
+lightly.
=back
-=head1 CAVEATS
+=head2 B<unimport>
-The role support now has only a few caveats. They are as follows:
+Moose::Role offers a way to remove the keywords it exports, through the
+C<unimport> method. You simply have to say C<no Moose::Role> at the bottom of
+your code for this to work.
-=over 4
+=head2 B<< Moose::Role->init_meta(for_class => $role, metaclass => $metaclass) >>
-=item *
+The C<init_meta> method sets up the metaclass object for the role
+specified by C<for_class>. It also injects a a C<meta> accessor into
+the role so you can get at this object.
-Roles cannot use the C<extends> keyword, it will throw an exception for now.
-The same is true of the C<augment> and C<inner> keywords (not sure those
-really make sense for roles). All other Moose keywords will be I<deferred>
-so that they can be applied to the consuming class.
+The default metaclass is L<Moose::Meta::Role>. You can specify an
+alternate metaclass with the C<metaclass> parameter.
-=item *
+=head1 METACLASS
-Role composition does it's best to B<not> be order sensitive when it comes
-to conflict resolution and requirements detection. However, it is order
-sensitive when it comes to method modifiers. All before/around/after modifiers
-are included whenever a role is composed into a class, and then are applied
-in the order the roles are used. This too means that there is no conflict for
-before/around/after modifiers as well.
+When you use Moose::Role, you can specify which metaclass to use:
-In most cases, this will be a non issue, however it is something to keep in
-mind when using method modifiers in a role. You should never assume any
-ordering.
+ use Moose::Role -metaclass => 'My::Meta::Role';
+
+You can also specify traits which will be applied to your role metaclass:
+
+ use Moose::Role -traits => 'My::Trait';
+
+This is very similar to the attribute traits feature. When you do
+this, your class's C<meta> object will have the specified traits
+applied to it. See L<Moose/Metaclass and Trait Name Resolution> for more
+details.
+
+=head1 APPLYING ROLES
+
+In addition to being applied to a class using the 'with' syntax (see
+L<Moose::Manual::Roles>) and using the L<Moose::Util> 'apply_all_roles'
+method, roles may also be applied to an instance of a class using
+L<Moose::Util> 'apply_all_roles' or the role's metaclass:
+
+ MyApp::Test::SomeRole->meta->apply( $instance );
+
+Doing this creates a new, mutable, anonymous subclass, applies the role to that,
+and reblesses. In a debugger, for example, you will see class names of the
+form C< Class::MOP::Class::__ANON__::SERIAL::6 >, which means that doing a 'ref'
+on your instance may not return what you expect. See L<Moose::Object> for 'DOES'.
+
+Additional params may be added to the new instance by providing 'rebless_params'.
+See L<Moose::Meta::Role::Application::ToInstance>.
+
+=head1 CAVEATS
+
+Role support has only a few caveats:
+
+=over 4
=item *
-The C<requires> keyword currently only works with actual methods. A method
-modifier (before/around/after and override) will not count as a fufillment
-of the requirement, and neither will an autogenerated accessor for an attribute.
+Roles cannot use the C<extends> keyword; it will throw an exception for now.
+The same is true of the C<augment> and C<inner> keywords (not sure those
+really make sense for roles). All other Moose keywords will be I<deferred>
+so that they can be applied to the consuming class.
-It is likely that the attribute accessors will eventually be allowed to fufill
-those requirements, either that or we will introduce a C<requires_attr> keyword
-of some kind instead. This descision has not yet been finalized.
+=item *
+
+Role composition does its best to B<not> be order-sensitive when it comes to
+conflict resolution and requirements detection. However, it is order-sensitive
+when it comes to method modifiers. All before/around/after modifiers are
+included whenever a role is composed into a class, and then applied in the order
+in which the roles are used. This also means that there is no conflict for
+before/around/after modifiers.
+
+In most cases, this will be a non-issue; however, it is something to keep in
+mind when using method modifiers in a role. You should never assume any
+ordering.
=back
=head1 BUGS
-All complex software has bugs lurking in it, and this module is no
-exception. If you find a bug please either email me, or add the bug
-to cpan-RT.
+See L<Moose/BUGS> for details on reporting bugs.
=head1 AUTHOR
=head1 COPYRIGHT AND LICENSE
-Copyright 2006 by Infinity Interactive, Inc.
+Copyright 2006-2010 by Infinity Interactive, Inc.
L<http://www.iinteractive.com>
This library is free software; you can redistribute it and/or modify
-it under the same terms as Perl itself.
+it under the same terms as Perl itself.
=cut
projects / gitmo/Moose.git / blobdiff