Commit | Line | Data |
e185c027 |
1 | |
2 | package Moose::Role; |
3 | |
4 | use strict; |
5 | use warnings; |
6 | |
e65dccbc |
7 | use Scalar::Util 'blessed'; |
e185c027 |
8 | use Carp 'confess'; |
9 | use Sub::Name 'subname'; |
10 | |
2d562421 |
11 | use Sub::Exporter; |
12 | |
4276ccb4 |
13 | our $VERSION = '0.05'; |
e185c027 |
14 | |
e65dccbc |
15 | use Moose (); |
16 | |
e185c027 |
17 | use Moose::Meta::Role; |
7eaef7ad |
18 | use Moose::Util::TypeConstraints; |
e185c027 |
19 | |
2d562421 |
20 | { |
21 | my ( $CALLER, %METAS ); |
22 | |
23 | sub _find_meta { |
7eaef7ad |
24 | my $role = $CALLER; |
2d562421 |
25 | |
7eaef7ad |
26 | return $METAS{$role} if exists $METAS{$role}; |
27 | |
28 | # make a subtype for each Moose class |
29 | subtype $role |
30 | => as 'Role' |
31 | => where { $_->does($role) } |
32 | unless find_type_constraint($role); |
2d562421 |
33 | |
34 | my $meta; |
7eaef7ad |
35 | if ($role->can('meta')) { |
36 | $meta = $role->meta(); |
2d562421 |
37 | (blessed($meta) && $meta->isa('Moose::Meta::Role')) |
38 | || confess "Whoops, not møøsey enough"; |
39 | } |
40 | else { |
7eaef7ad |
41 | $meta = Moose::Meta::Role->new(role_name => $role); |
2d562421 |
42 | $meta->_role_meta->add_method('meta' => sub { $meta }) |
43 | } |
44 | |
7eaef7ad |
45 | return $METAS{$role} = $meta; |
2d562421 |
46 | } |
47 | |
e185c027 |
48 | |
9d3188da |
49 | my %exports = ( |
2d562421 |
50 | extends => sub { |
51 | my $meta = _find_meta(); |
52 | return subname 'Moose::Role::extends' => sub { |
53 | confess "Moose::Role does not currently support 'extends'" |
54 | }; |
55 | }, |
56 | with => sub { |
57 | my $meta = _find_meta(); |
68117c45 |
58 | return subname 'Moose::Role::with' => sub (@) { |
d05cd563 |
59 | my (@roles) = @_; |
68117c45 |
60 | confess "Must specify at least one role" unless @roles; |
d05cd563 |
61 | Moose::_load_all_classes(@roles); |
62 | ($_->can('meta') && $_->meta->isa('Moose::Meta::Role')) |
63 | || confess "You can only consume roles, $_ is not a Moose role" |
64 | foreach @roles; |
65 | if (scalar @roles == 1) { |
66 | $roles[0]->meta->apply($meta); |
67 | } |
68 | else { |
69 | Moose::Meta::Role->combine( |
70 | map { $_->meta } @roles |
71 | )->apply($meta); |
72 | } |
2d562421 |
73 | }; |
74 | }, |
75 | requires => sub { |
76 | my $meta = _find_meta(); |
68117c45 |
77 | return subname 'Moose::Role::requires' => sub (@) { |
78 | confess "Must specify at least one method" unless @_; |
2d562421 |
79 | $meta->add_required_methods(@_); |
80 | }; |
81 | }, |
d79e62fd |
82 | excludes => sub { |
83 | my $meta = _find_meta(); |
68117c45 |
84 | return subname 'Moose::Role::excludes' => sub (@) { |
85 | confess "Must specify at least one role" unless @_; |
d79e62fd |
86 | $meta->add_excluded_roles(@_); |
87 | }; |
88 | }, |
2d562421 |
89 | has => sub { |
90 | my $meta = _find_meta(); |
2c0cbef7 |
91 | return subname 'Moose::Role::has' => sub ($;%) { |
2d562421 |
92 | my ($name, %options) = @_; |
93 | $meta->add_attribute($name, %options) |
94 | }; |
95 | }, |
96 | before => sub { |
97 | my $meta = _find_meta(); |
2c0cbef7 |
98 | return subname 'Moose::Role::before' => sub (@&) { |
06b30515 |
99 | confess "Moose::Role does not currently support 'before'"; |
2d562421 |
100 | }; |
101 | }, |
102 | after => sub { |
103 | my $meta = _find_meta(); |
2c0cbef7 |
104 | return subname 'Moose::Role::after' => sub (@&) { |
06b30515 |
105 | confess "Moose::Role does not currently support 'after'"; |
2d562421 |
106 | }; |
107 | }, |
108 | around => sub { |
109 | my $meta = _find_meta(); |
2c0cbef7 |
110 | return subname 'Moose::Role::around' => sub (@&) { |
06b30515 |
111 | confess "Moose::Role does not currently support 'around'"; |
2d562421 |
112 | }; |
113 | }, |
114 | super => sub { |
115 | my $meta = _find_meta(); |
8256469a |
116 | return subname 'Moose::Role::super' => sub { |
117 | confess "Moose::Role cannot support 'super'"; |
118 | }; |
2d562421 |
119 | }, |
120 | override => sub { |
121 | my $meta = _find_meta(); |
2c0cbef7 |
122 | return subname 'Moose::Role::override' => sub ($&) { |
06b30515 |
123 | confess "Moose::Role cannot support 'override'"; |
2d562421 |
124 | }; |
125 | }, |
126 | inner => sub { |
127 | my $meta = _find_meta(); |
128 | return subname 'Moose::Role::inner' => sub { |
06b30515 |
129 | confess "Moose::Role cannot support 'inner'"; |
2d562421 |
130 | }; |
131 | }, |
132 | augment => sub { |
133 | my $meta = _find_meta(); |
134 | return subname 'Moose::Role::augment' => sub { |
06b30515 |
135 | confess "Moose::Role cannot support 'augment'"; |
2d562421 |
136 | }; |
137 | }, |
138 | confess => sub { |
139 | return \&Carp::confess; |
140 | }, |
141 | blessed => sub { |
142 | return \&Scalar::Util::blessed; |
143 | } |
144 | ); |
145 | |
146 | my $exporter = Sub::Exporter::build_exporter({ |
147 | exports => \%exports, |
148 | groups => { |
149 | default => [':all'] |
150 | } |
151 | }); |
152 | |
153 | sub import { |
154 | $CALLER = caller(); |
c235cd98 |
155 | |
156 | strict->import; |
157 | warnings->import; |
2d562421 |
158 | |
159 | # we should never export to main |
160 | return if $CALLER eq 'main'; |
161 | |
162 | goto $exporter; |
163 | }; |
164 | |
e185c027 |
165 | } |
166 | |
167 | 1; |
168 | |
169 | __END__ |
170 | |
171 | =pod |
172 | |
173 | =head1 NAME |
174 | |
175 | Moose::Role - The Moose Role |
176 | |
76d37e5a |
177 | =head1 SYNOPSIS |
178 | |
179 | package Eq; |
180 | use strict; |
181 | use warnings; |
182 | use Moose::Role; |
183 | |
e46edf94 |
184 | requires 'equal'; |
76d37e5a |
185 | |
186 | sub no_equal { |
187 | my ($self, $other) = @_; |
188 | !$self->equal($other); |
189 | } |
190 | |
191 | # ... then in your classes |
192 | |
193 | package Currency; |
194 | use strict; |
195 | use warnings; |
196 | use Moose; |
197 | |
198 | with 'Eq'; |
199 | |
200 | sub equal { |
201 | my ($self, $other) = @_; |
bdabd620 |
202 | $self->as_float == $other->as_float; |
76d37e5a |
203 | } |
204 | |
e185c027 |
205 | =head1 DESCRIPTION |
206 | |
2c0cbef7 |
207 | Role support in Moose is coming along quite well. It's best documentation |
208 | is still the the test suite, but it is fairly safe to assume Perl 6 style |
209 | behavior, and then either refer to the test suite, or ask questions on |
210 | #moose if something doesn't quite do what you expect. More complete |
211 | documentation is planned and will be included with the next official |
212 | (non-developer) release. |
76d37e5a |
213 | |
2c0cbef7 |
214 | =head1 EXPORTED FUNCTIONS |
215 | |
216 | Currently Moose::Role supports all of the functions that L<Moose> exports, |
217 | but differs slightly in how some items are handled (see L<CAVEATS> below |
218 | for details). |
76d37e5a |
219 | |
2c0cbef7 |
220 | Moose::Role also offers two role specific keyword exports: |
e185c027 |
221 | |
222 | =over 4 |
223 | |
2c0cbef7 |
224 | =item B<requires (@method_names)> |
76d37e5a |
225 | |
9e93dd19 |
226 | Roles can require that certain methods are implemented by any class which |
227 | C<does> the role. |
228 | |
2c0cbef7 |
229 | =item B<excludes (@role_names)> |
230 | |
9e93dd19 |
231 | Roles can C<exclude> other roles, in effect saying "I can never be combined |
232 | with these C<@role_names>". This is a feature which should not be used |
233 | lightly. |
234 | |
2c0cbef7 |
235 | =back |
236 | |
237 | =head1 CAVEATS |
238 | |
239 | The role support now has only a few caveats. They are as follows: |
240 | |
241 | =over 4 |
76d37e5a |
242 | |
76d37e5a |
243 | =item * |
244 | |
245 | Roles cannot use the C<extends> keyword, it will throw an exception for now. |
246 | The same is true of the C<augment> and C<inner> keywords (not sure those |
247 | really make sense for roles). All other Moose keywords will be I<deferred> |
248 | so that they can be applied to the consuming class. |
249 | |
2c0cbef7 |
250 | =item * |
251 | |
252 | Role composition does it's best to B<not> be order sensitive when it comes |
253 | to conflict resolution and requirements detection. However, it is order |
254 | sensitive when it comes to method modifiers. All before/around/after modifiers |
255 | are included whenever a role is composed into a class, and then are applied |
256 | in the order the roles are used. This too means that there is no conflict for |
257 | before/around/after modifiers as well. |
258 | |
259 | In most cases, this will be a non issue, however it is something to keep in |
260 | mind when using method modifiers in a role. You should never assume any |
261 | ordering. |
262 | |
263 | =item * |
264 | |
265 | The C<requires> keyword currently only works with actual methods. A method |
266 | modifier (before/around/after and override) will not count as a fufillment |
267 | of the requirement, and neither will an autogenerated accessor for an attribute. |
268 | |
269 | It is likely that the attribute accessors will eventually be allowed to fufill |
270 | those requirements, either that or we will introduce a C<requires_attr> keyword |
271 | of some kind instead. This descision has not yet been finalized. |
272 | |
e185c027 |
273 | =back |
274 | |
275 | =head1 BUGS |
276 | |
277 | All complex software has bugs lurking in it, and this module is no |
278 | exception. If you find a bug please either email me, or add the bug |
279 | to cpan-RT. |
280 | |
281 | =head1 AUTHOR |
282 | |
283 | Stevan Little E<lt>stevan@iinteractive.comE<gt> |
284 | |
db1ab48d |
285 | Christian Hansen E<lt>chansen@cpan.orgE<gt> |
98aae381 |
286 | |
e185c027 |
287 | =head1 COPYRIGHT AND LICENSE |
288 | |
289 | Copyright 2006 by Infinity Interactive, Inc. |
290 | |
291 | L<http://www.iinteractive.com> |
292 | |
293 | This library is free software; you can redistribute it and/or modify |
294 | it under the same terms as Perl itself. |
295 | |
68117c45 |
296 | =cut |