1 package Moose::Meta::Role::Application::ToRole;
8 use Scalar::Util 'blessed';
12 our $VERSION = '0.55_01';
13 $VERSION = eval $VERSION;
14 our $AUTHORITY = 'cpan:STEVAN';
16 use base 'Moose::Meta::Role::Application';
19 my ($self, $role1, $role2) = @_;
20 $self->SUPER::apply($role1, $role2);
21 $role2->add_role($role1);
24 sub check_role_exclusions {
25 my ($self, $role1, $role2) = @_;
26 confess "Conflict detected: " . $role2->name . " excludes role '" . $role1->name . "'"
27 if $role2->excludes_role($role1->name);
28 foreach my $excluded_role_name ($role1->get_excluded_roles_list) {
29 confess "The class " . $role2->name . " does the excluded role '$excluded_role_name'"
30 if $role2->does_role($excluded_role_name);
31 $role2->add_excluded_roles($excluded_role_name);
35 sub check_required_methods {
36 my ($self, $role1, $role2) = @_;
37 foreach my $required_method_name ($role1->get_required_method_list) {
39 next if $self->is_aliased_method($required_method_name);
41 $role2->add_required_methods($required_method_name)
42 unless $role2->find_method_by_name($required_method_name);
46 sub check_required_attributes {
50 sub apply_attributes {
51 my ($self, $role1, $role2) = @_;
52 foreach my $attribute_name ($role1->get_attribute_list) {
53 # it if it has one already
54 if ($role2->has_attribute($attribute_name) &&
55 # make sure we haven't seen this one already too
56 $role2->get_attribute($attribute_name) != $role1->get_attribute($attribute_name)) {
57 confess "Role '" . $role1->name . "' has encountered an attribute conflict " .
58 "during composition. This is fatal error and cannot be disambiguated.";
61 $role2->add_attribute(
63 $role1->get_attribute($attribute_name)
70 my ($self, $role1, $role2) = @_;
71 foreach my $method_name ($role1->get_method_list) {
73 next if $self->is_method_excluded($method_name);
75 if ($self->is_method_aliased($method_name)) {
76 my $aliased_method_name = $self->get_method_aliases->{$method_name};
77 # it if it has one already
78 if ($role2->has_method($aliased_method_name) &&
79 # and if they are not the same thing ...
80 $role2->get_method($aliased_method_name)->body != $role1->get_method($method_name)->body) {
81 confess "Cannot create a method alias if a local method of the same name exists";
86 $role1->get_method($method_name)
89 if (!$role2->has_method($method_name)) {
90 $role2->add_required_methods($method_name);
96 # it if it has one already
97 if ($role2->has_method($method_name) &&
98 # and if they are not the same thing ...
99 $role2->get_method($method_name)->body != $role1->get_method($method_name)->body) {
100 # method conflicts between roles result
101 # in the method becoming a requirement
102 $role2->add_required_methods($method_name);
105 # add it, although it could be overriden
106 $role2->alias_method(
108 $role1->get_method($method_name)
116 sub apply_override_method_modifiers {
117 my ($self, $role1, $role2) = @_;
118 foreach my $method_name ($role1->get_method_modifier_list('override')) {
119 # it if it has one already then ...
120 if ($role2->has_method($method_name)) {
121 # if it is being composed into another role
122 # we have a conflict here, because you cannot
123 # combine an overriden method with a locally
125 confess "Role '" . $role1->name . "' has encountered an 'override' method conflict " .
126 "during composition (A local method of the same name as been found). This " .
130 # if we are a role, we need to make sure
131 # we dont have a conflict with the role
132 # we are composing into
133 if ($role2->has_override_method_modifier($method_name) &&
134 $role2->get_override_method_modifier($method_name) != $role2->get_override_method_modifier($method_name)) {
135 confess "Role '" . $role1->name . "' has encountered an 'override' method conflict " .
136 "during composition (Two 'override' methods of the same name encountered). " .
137 "This is fatal error.";
140 # if there is no conflict,
141 # just add it to the role
142 $role2->add_override_method_modifier(
144 $role1->get_override_method_modifier($method_name)
151 sub apply_method_modifiers {
152 my ($self, $modifier_type, $role1, $role2) = @_;
153 my $add = "add_${modifier_type}_method_modifier";
154 my $get = "get_${modifier_type}_method_modifiers";
155 foreach my $method_name ($role1->get_method_modifier_list($modifier_type)) {
159 ) foreach $role1->$get($method_name);
172 Moose::Meta::Role::Application::ToRole - Compose a role into another role
186 =item B<check_role_exclusions>
188 =item B<check_required_methods>
190 =item B<check_required_attributes>
192 =item B<apply_attributes>
194 =item B<apply_methods>
196 =item B<apply_method_modifiers>
198 =item B<apply_override_method_modifiers>
204 All complex software has bugs lurking in it, and this module is no
205 exception. If you find a bug please either email me, or add the bug
210 Stevan Little E<lt>stevan@iinteractive.comE<gt>
212 =head1 COPYRIGHT AND LICENSE
214 Copyright 2006-2008 by Infinity Interactive, Inc.
216 L<http://www.iinteractive.com>
218 This library is free software; you can redistribute it and/or modify
219 it under the same terms as Perl itself.