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package Moose::Meta::Role::Application::ToRole;
use strict;
use warnings;
use metaclass;
use Scalar::Util 'blessed';
our $VERSION = '1.09';
$VERSION = eval $VERSION;
our $AUTHORITY = 'cpan:STEVAN';
use base 'Moose::Meta::Role::Application';
sub apply {
my ($self, $role1, $role2) = @_;
$self->SUPER::apply($role1, $role2);
$role2->add_role($role1);
}
sub check_role_exclusions {
my ($self, $role1, $role2) = @_;
if ( $role2->excludes_role($role1->name) ) {
require Moose;
Moose->throw_error("Conflict detected: " . $role2->name . " excludes role '" . $role1->name . "'");
}
foreach my $excluded_role_name ($role1->get_excluded_roles_list) {
if ( $role2->does_role($excluded_role_name) ) {
require Moose;
Moose->throw_error("The class " . $role2->name . " does the excluded role '$excluded_role_name'");
}
$role2->add_excluded_roles($excluded_role_name);
}
}
sub check_required_methods {
my ($self, $role1, $role2) = @_;
foreach my $required_method ($role1->get_required_method_list) {
my $required_method_name = $required_method->name;
next if $self->is_aliased_method($required_method_name);
$role2->add_required_methods($required_method)
unless $role2->find_method_by_name($required_method_name);
}
}
sub check_required_attributes {
}
sub apply_attributes {
my ($self, $role1, $role2) = @_;
foreach my $attribute_name ($role1->get_attribute_list) {
# it if it has one already
if ($role2->has_attribute($attribute_name) &&
# make sure we haven't seen this one already too
$role2->get_attribute($attribute_name) != $role1->get_attribute($attribute_name)) {
require Moose;
Moose->throw_error("Role '" . $role1->name . "' has encountered an attribute conflict " .
"during composition. This is fatal error and cannot be disambiguated.");
}
else {
$role2->add_attribute(
$role1->get_attribute($attribute_name)->clone
);
}
}
}
sub apply_methods {
my ($self, $role1, $role2) = @_;
foreach my $method_name ($role1->get_method_list) {
next if $method_name eq 'meta';
unless ( $self->is_method_excluded($method_name) ) {
if ( $role2->has_method($method_name)
&& $role2->get_method($method_name)->body
!= $role1->get_method($method_name)->body ) {
# method conflicts between roles result in the method becoming
# a requirement
$role2->add_conflicting_method(
name => $method_name,
roles => [ $role1->name, $role2->name ],
);
}
else {
$role2->add_method(
$method_name,
$role1->get_method($method_name)
);
}
}
if ($self->is_method_aliased($method_name)) {
my $aliased_method_name = $self->get_method_aliases->{$method_name};
if ($role2->has_method($aliased_method_name) &&
$role2->get_method($aliased_method_name)->body != $role1->get_method($method_name)->body) {
require Moose;
Moose->throw_error("Cannot create a method alias if a local method of the same name exists");
}
$role2->add_method(
$aliased_method_name,
$role1->get_method($method_name)
);
if (!$role2->has_method($method_name)) {
$role2->add_required_methods($method_name)
unless $self->is_method_excluded($method_name);
}
}
}
}
sub apply_override_method_modifiers {
my ($self, $role1, $role2) = @_;
foreach my $method_name ($role1->get_method_modifier_list('override')) {
# it if it has one already then ...
if ($role2->has_method($method_name)) {
# if it is being composed into another role
# we have a conflict here, because you cannot
# combine an overridden method with a locally
# defined one
require Moose;
Moose->throw_error("Role '" . $role1->name . "' has encountered an 'override' method conflict " .
"during composition (A local method of the same name as been found). This " .
"is fatal error.");
}
else {
# if we are a role, we need to make sure
# we dont have a conflict with the role
# we are composing into
if ($role2->has_override_method_modifier($method_name) &&
$role2->get_override_method_modifier($method_name) != $role2->get_override_method_modifier($method_name)) {
require Moose;
Moose->throw_error("Role '" . $role1->name . "' has encountered an 'override' method conflict " .
"during composition (Two 'override' methods of the same name encountered). " .
"This is fatal error.");
}
else {
# if there is no conflict,
# just add it to the role
$role2->add_override_method_modifier(
$method_name,
$role1->get_override_method_modifier($method_name)
);
}
}
}
}
sub apply_method_modifiers {
my ($self, $modifier_type, $role1, $role2) = @_;
my $add = "add_${modifier_type}_method_modifier";
my $get = "get_${modifier_type}_method_modifiers";
foreach my $method_name ($role1->get_method_modifier_list($modifier_type)) {
$role2->$add(
$method_name,
$_
) foreach $role1->$get($method_name);
}
}
1;
__END__
=pod
=head1 NAME
Moose::Meta::Role::Application::ToRole - Compose a role into another role
=head1 DESCRIPTION
=head2 METHODS
=over 4
=item B<new>
=item B<meta>
=item B<apply>
=item B<check_role_exclusions>
=item B<check_required_methods>
=item B<check_required_attributes>
=item B<apply_attributes>
=item B<apply_methods>
=item B<apply_method_modifiers>
=item B<apply_override_method_modifiers>
=back
=head1 BUGS
See L<Moose/BUGS> for details on reporting bugs.
=head1 AUTHOR
Stevan Little E<lt>stevan@iinteractive.comE<gt>
=head1 COPYRIGHT AND LICENSE
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.
=cut
|
