-
package Moose::Role;
-
use strict;
use warnings;
use Scalar::Util 'blessed';
-use Carp 'confess', 'croak';
+use Carp 'croak';
-use Data::OptList;
use Sub::Exporter;
-our $VERSION = '0.54';
+our $VERSION = '0.91';
+$VERSION = eval $VERSION;
our $AUTHORITY = 'cpan:STEVAN';
use Moose ();
use Moose::Util ();
+use Moose::Exporter;
use Moose::Meta::Role;
use Moose::Util::TypeConstraints;
-{
- my ( $CALLER, %METAS );
+sub extends {
+ croak "Roles do not support 'extends' (you can use 'with' to specialize a role)";
+}
- sub _find_meta {
- my $role = $CALLER;
+sub with {
+ Moose::Util::apply_all_roles( shift, @_ );
+}
- return $METAS{$role} if exists $METAS{$role};
+sub requires {
+ my $meta = shift;
+ croak "Must specify at least one method" unless @_;
+ $meta->add_required_methods(@_);
+}
- # make a subtype for each Moose class
- role_type $role unless find_type_constraint($role);
+sub excludes {
+ my $meta = shift;
+ croak "Must specify at least one role" unless @_;
+ $meta->add_excluded_roles(@_);
+}
- 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->alias_method('meta' => sub { $meta });
- }
+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;
+}
- return $METAS{$role} = $meta;
+sub _add_method_modifier {
+ my $type = shift;
+ my $meta = shift;
+ my $code = pop @_;
+
+ for (@_) {
+ croak "Roles do not currently support "
+ . ref($_)
+ . " references for $type method modifiers"
+ if ref $_;
+ my $add_method = "add_${type}_method_modifier";
+ $meta->$add_method( $_, $code );
}
+}
+sub before { _add_method_modifier('before', @_) }
- my %exports = (
- extends => sub {
- my $meta = _find_meta();
- return Class::MOP::subname('Moose::Role::extends' => sub {
- croak "Roles do not currently support 'extends'"
- });
- },
- with => sub {
- my $meta = _find_meta();
- return Class::MOP::subname('Moose::Role::with' => sub (@) {
- Moose::Util::apply_all_roles($meta, @_)
- });
- },
- requires => sub {
- my $meta = _find_meta();
- return Class::MOP::subname('Moose::Role::requires' => sub (@) {
- croak "Must specify at least one method" unless @_;
- $meta->add_required_methods(@_);
- });
- },
- excludes => sub {
- my $meta = _find_meta();
- return Class::MOP::subname('Moose::Role::excludes' => sub (@) {
- croak "Must specify at least one role" unless @_;
- $meta->add_excluded_roles(@_);
- });
- },
- has => sub {
- my $meta = _find_meta();
- return Class::MOP::subname('Moose::Role::has' => sub ($;%) {
- my $name = shift;
- croak 'Usage: has \'name\' => ( key => value, ... )' if @_ == 1;
- my %options = @_;
- my $attrs = ( ref($name) eq 'ARRAY' ) ? $name : [ ($name) ];
- $meta->add_attribute( $_, %options ) for @$attrs;
- });
- },
- before => sub {
- my $meta = _find_meta();
- return Class::MOP::subname('Moose::Role::before' => sub (@&) {
- my $code = pop @_;
- do {
- croak "Moose::Role do not currently support "
- . ref($_)
- . " references for before method modifiers"
- if ref $_;
- $meta->add_before_method_modifier($_, $code)
- } for @_;
- });
- },
- after => sub {
- my $meta = _find_meta();
- return Class::MOP::subname('Moose::Role::after' => sub (@&) {
- my $code = pop @_;
- do {
- croak "Moose::Role do not currently support "
- . ref($_)
- . " references for after method modifiers"
- if ref $_;
- $meta->add_after_method_modifier($_, $code)
- } for @_;
- });
- },
- around => sub {
- my $meta = _find_meta();
- return Class::MOP::subname('Moose::Role::around' => sub (@&) {
- my $code = pop @_;
- do {
- croak "Moose::Role do not currently support "
- . ref($_)
- . " references for around method modifiers"
- if ref $_;
- $meta->add_around_method_modifier($_, $code)
- } for @_;
- });
- },
- # see Moose.pm for discussion
- super => sub {
- return Class::MOP::subname('Moose::Role::super' => sub {
- return unless $Moose::SUPER_BODY; $Moose::SUPER_BODY->(@Moose::SUPER_ARGS)
- });
- },
- override => sub {
- my $meta = _find_meta();
- return Class::MOP::subname('Moose::Role::override' => sub ($&) {
- my ($name, $code) = @_;
- $meta->add_override_method_modifier($name, $code);
- });
- },
- inner => sub {
- my $meta = _find_meta();
- return Class::MOP::subname('Moose::Role::inner' => sub {
- croak "Moose::Role cannot support 'inner'";
- });
- },
- augment => sub {
- my $meta = _find_meta();
- return Class::MOP::subname('Moose::Role::augment' => sub {
- croak "Moose::Role cannot support 'augment'";
- });
- },
- confess => sub {
- return \&Carp::confess;
- },
- blessed => sub {
- return \&Scalar::Util::blessed;
- }
- );
+sub after { _add_method_modifier('after', @_) }
- my $exporter = Sub::Exporter::build_exporter({
- exports => \%exports,
- groups => {
- default => [':all']
- }
- });
+sub around { _add_method_modifier('around', @_) }
- sub import {
- $CALLER =
- ref $_[1] && defined $_[1]->{into} ? $_[1]->{into}
- : ref $_[1]
- && defined $_[1]->{into_level} ? caller( $_[1]->{into_level} )
- : caller();
+# see Moose.pm for discussion
+sub super {
+ return unless $Moose::SUPER_BODY;
+ $Moose::SUPER_BODY->(@Moose::SUPER_ARGS);
+}
- # this works because both pragmas set $^H (see perldoc perlvar)
- # which affects the current compilation - i.e. the file who use'd
- # us - which is why we don't need to do anything special to make
- # it affect that file rather than this one (which is already compiled)
+sub override {
+ my $meta = shift;
+ my ( $name, $code ) = @_;
+ $meta->add_override_method_modifier( $name, $code );
+}
- strict->import;
- warnings->import;
+sub inner {
+ croak "Roles cannot support 'inner'";
+}
- # we should never export to main
- return if $CALLER eq 'main';
+sub augment {
+ croak "Roles cannot support 'augment'";
+}
- goto $exporter;
- };
+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");
+ }
- sub unimport {
- no strict 'refs';
- my $class = Moose::_get_caller(@_);
+ my $metaclass = $args{metaclass} || "Moose::Meta::Role";
- # loop through the exports ...
- foreach my $name ( keys %exports ) {
+ # make a subtype for each Moose class
+ role_type $role unless find_type_constraint($role);
- # if we find one ...
- if ( defined &{ $class . '::' . $name } ) {
- my $keyword = \&{ $class . '::' . $name };
+ # FIXME copy from Moose.pm
+ my $meta;
+ if ($role->can('meta')) {
+ $meta = $role->meta();
- # make sure it is from Moose::Role
- my ($pkg_name) = Class::MOP::get_code_info($keyword);
- next if $pkg_name ne 'Moose::Role';
+ unless ( blessed($meta) && $meta->isa('Moose::Meta::Role') ) {
+ require Moose;
+ Moose->throw_error("You already have a &meta function, but it does not return a Moose::Meta::Role");
+ }
+ }
+ else {
+ $meta = $metaclass->initialize($role);
- # and if it is from Moose::Role then undef the slot
- delete ${ $class . '::' }{$name};
+ $meta->add_method(
+ 'meta' => sub {
+ # re-initialize so it inherits properly
+ $metaclass->initialize( ref($_[0]) || $_[0] );
}
- }
+ );
}
+
+ return $meta;
}
1;
=head1 DESCRIPTION
-Role support in Moose is pretty solid at this point. However, the best
-documentation is still the the test suite. 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.
-
-We are planning writing some more documentation in the near future, but nothing
-is ready yet, sorry.
+The concept of roles is documented in L<Moose::Manual::Roles>. This document
+serves as API documentation.
=head1 EXPORTED FUNCTIONS
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
C<unimport> method. You simply have to say C<no Moose::Role> at the bottom of
your code for this to work.
+=head2 B<< Moose::Role->init_meta(for_class => $role, metaclass => $metaclass) >>
+
+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.
+
+The default metaclass is L<Moose::Meta::Role>. You can specify an
+alternate metaclass with the C<metaclass> parameter.
+
+=head1 METACLASS
+
+When you use Moose::Role, you can specify which metaclass to use:
+
+ 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:
mind when using method modifiers in a role. You should never assume any
ordering.
-=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.
-
-It is likely that attribute accessors will eventually be allowed to fufill those
-requirements, or we will introduce a C<requires_attr> keyword of some kind
-instead. This decision has not yet been finalized.
-
=back
=head1 BUGS
=head1 COPYRIGHT AND LICENSE
-Copyright 2006-2008 by Infinity Interactive, Inc.
+Copyright 2006-2009 by Infinity Interactive, Inc.
L<http://www.iinteractive.com>
projects / gitmo/Moose.git / blobdiff