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 | |
d44714be |
13 | our $VERSION = '0.07'; |
14 | our $AUTHORITY = 'cpan:STEVAN'; |
e185c027 |
15 | |
e65dccbc |
16 | use Moose (); |
17 | |
e185c027 |
18 | use Moose::Meta::Role; |
7eaef7ad |
19 | use Moose::Util::TypeConstraints; |
e185c027 |
20 | |
2d562421 |
21 | { |
22 | my ( $CALLER, %METAS ); |
23 | |
24 | sub _find_meta { |
7eaef7ad |
25 | my $role = $CALLER; |
2d562421 |
26 | |
7eaef7ad |
27 | return $METAS{$role} if exists $METAS{$role}; |
28 | |
29 | # make a subtype for each Moose class |
30 | subtype $role |
31 | => as 'Role' |
32 | => where { $_->does($role) } |
1f779926 |
33 | => optimize_as { blessed($_[0]) && $_[0]->can('does') && $_[0]->does($role) } |
7eaef7ad |
34 | unless find_type_constraint($role); |
2d562421 |
35 | |
36 | my $meta; |
7eaef7ad |
37 | if ($role->can('meta')) { |
38 | $meta = $role->meta(); |
2d562421 |
39 | (blessed($meta) && $meta->isa('Moose::Meta::Role')) |
68efb014 |
40 | || confess "You already have a &meta function, but it does not return a Moose::Meta::Role"; |
2d562421 |
41 | } |
42 | else { |
68efb014 |
43 | $meta = Moose::Meta::Role->initialize($role); |
44 | $meta->Moose::Meta::Class::add_method('meta' => sub { $meta }) |
2d562421 |
45 | } |
46 | |
7eaef7ad |
47 | return $METAS{$role} = $meta; |
2d562421 |
48 | } |
49 | |
e185c027 |
50 | |
9d3188da |
51 | my %exports = ( |
2d562421 |
52 | extends => sub { |
53 | my $meta = _find_meta(); |
54 | return subname 'Moose::Role::extends' => sub { |
55 | confess "Moose::Role does not currently support 'extends'" |
56 | }; |
57 | }, |
58 | with => sub { |
59 | my $meta = _find_meta(); |
68117c45 |
60 | return subname 'Moose::Role::with' => sub (@) { |
d05cd563 |
61 | my (@roles) = @_; |
68117c45 |
62 | confess "Must specify at least one role" unless @roles; |
1eaed09d |
63 | Class::MOP::load_class($_) for @roles; |
d05cd563 |
64 | ($_->can('meta') && $_->meta->isa('Moose::Meta::Role')) |
65 | || confess "You can only consume roles, $_ is not a Moose role" |
66 | foreach @roles; |
67 | if (scalar @roles == 1) { |
68 | $roles[0]->meta->apply($meta); |
69 | } |
70 | else { |
71 | Moose::Meta::Role->combine( |
72 | map { $_->meta } @roles |
73 | )->apply($meta); |
74 | } |
2d562421 |
75 | }; |
76 | }, |
77 | requires => sub { |
78 | my $meta = _find_meta(); |
68117c45 |
79 | return subname 'Moose::Role::requires' => sub (@) { |
80 | confess "Must specify at least one method" unless @_; |
2d562421 |
81 | $meta->add_required_methods(@_); |
82 | }; |
83 | }, |
d79e62fd |
84 | excludes => sub { |
85 | my $meta = _find_meta(); |
68117c45 |
86 | return subname 'Moose::Role::excludes' => sub (@) { |
87 | confess "Must specify at least one role" unless @_; |
d79e62fd |
88 | $meta->add_excluded_roles(@_); |
89 | }; |
90 | }, |
2d562421 |
91 | has => sub { |
92 | my $meta = _find_meta(); |
2c0cbef7 |
93 | return subname 'Moose::Role::has' => sub ($;%) { |
2d562421 |
94 | my ($name, %options) = @_; |
95 | $meta->add_attribute($name, %options) |
96 | }; |
97 | }, |
98 | before => sub { |
99 | my $meta = _find_meta(); |
2c0cbef7 |
100 | return subname 'Moose::Role::before' => sub (@&) { |
0558683c |
101 | my $code = pop @_; |
102 | $meta->add_before_method_modifier($_, $code) for @_; |
2d562421 |
103 | }; |
104 | }, |
105 | after => sub { |
106 | my $meta = _find_meta(); |
2c0cbef7 |
107 | return subname 'Moose::Role::after' => sub (@&) { |
0558683c |
108 | my $code = pop @_; |
109 | $meta->add_after_method_modifier($_, $code) for @_; |
2d562421 |
110 | }; |
111 | }, |
112 | around => sub { |
113 | my $meta = _find_meta(); |
2c0cbef7 |
114 | return subname 'Moose::Role::around' => sub (@&) { |
0558683c |
115 | my $code = pop @_; |
116 | $meta->add_around_method_modifier($_, $code) for @_; |
2d562421 |
117 | }; |
118 | }, |
119 | super => sub { |
52c7c330 |
120 | { |
121 | no strict 'refs'; |
122 | $Moose::SUPER_SLOT{$CALLER} = \*{"${CALLER}::super"}; |
123 | } |
2d562421 |
124 | my $meta = _find_meta(); |
0558683c |
125 | return subname 'Moose::Role::super' => sub {}; |
2d562421 |
126 | }, |
127 | override => sub { |
128 | my $meta = _find_meta(); |
2c0cbef7 |
129 | return subname 'Moose::Role::override' => sub ($&) { |
0558683c |
130 | my ($name, $code) = @_; |
131 | $meta->add_override_method_modifier($name, $code); |
2d562421 |
132 | }; |
133 | }, |
134 | inner => sub { |
135 | my $meta = _find_meta(); |
136 | return subname 'Moose::Role::inner' => sub { |
0558683c |
137 | confess "Moose::Role cannot support 'inner'"; |
2d562421 |
138 | }; |
139 | }, |
140 | augment => sub { |
141 | my $meta = _find_meta(); |
142 | return subname 'Moose::Role::augment' => sub { |
06b30515 |
143 | confess "Moose::Role cannot support 'augment'"; |
2d562421 |
144 | }; |
145 | }, |
146 | confess => sub { |
147 | return \&Carp::confess; |
148 | }, |
149 | blessed => sub { |
150 | return \&Scalar::Util::blessed; |
151 | } |
152 | ); |
153 | |
154 | my $exporter = Sub::Exporter::build_exporter({ |
155 | exports => \%exports, |
156 | groups => { |
157 | default => [':all'] |
158 | } |
159 | }); |
160 | |
161 | sub import { |
162 | $CALLER = caller(); |
c235cd98 |
163 | |
164 | strict->import; |
165 | warnings->import; |
2d562421 |
166 | |
167 | # we should never export to main |
168 | return if $CALLER eq 'main'; |
169 | |
170 | goto $exporter; |
171 | }; |
172 | |
e185c027 |
173 | } |
174 | |
175 | 1; |
176 | |
177 | __END__ |
178 | |
179 | =pod |
180 | |
181 | =head1 NAME |
182 | |
183 | Moose::Role - The Moose Role |
184 | |
76d37e5a |
185 | =head1 SYNOPSIS |
186 | |
187 | package Eq; |
85424612 |
188 | use Moose::Role; # automatically turns on strict and warnings |
76d37e5a |
189 | |
e46edf94 |
190 | requires 'equal'; |
76d37e5a |
191 | |
192 | sub no_equal { |
193 | my ($self, $other) = @_; |
194 | !$self->equal($other); |
195 | } |
196 | |
197 | # ... then in your classes |
198 | |
199 | package Currency; |
85424612 |
200 | use Moose; # automatically turns on strict and warnings |
76d37e5a |
201 | |
202 | with 'Eq'; |
203 | |
204 | sub equal { |
205 | my ($self, $other) = @_; |
bdabd620 |
206 | $self->as_float == $other->as_float; |
76d37e5a |
207 | } |
208 | |
e185c027 |
209 | =head1 DESCRIPTION |
210 | |
85424612 |
211 | Role support in Moose is pretty solid at this point. However, the best |
212 | documentation is still the the test suite. It is fairly safe to assume Perl 6 |
213 | style behavior and then either refer to the test suite, or ask questions on |
214 | #moose if something doesn't quite do what you expect. |
d44714be |
215 | |
85424612 |
216 | We are planning writing some more documentation in the near future, but nothing |
217 | is ready yet, sorry. |
76d37e5a |
218 | |
2c0cbef7 |
219 | =head1 EXPORTED FUNCTIONS |
220 | |
85424612 |
221 | Moose::Role currently supports all of the functions that L<Moose> exports, but |
222 | differs slightly in how some items are handled (see L<CAVEATS> below for |
223 | details). |
76d37e5a |
224 | |
85424612 |
225 | Moose::Role also offers two role-specific keyword exports: |
e185c027 |
226 | |
227 | =over 4 |
228 | |
2c0cbef7 |
229 | =item B<requires (@method_names)> |
76d37e5a |
230 | |
9e93dd19 |
231 | Roles can require that certain methods are implemented by any class which |
85424612 |
232 | C<does> the role. |
9e93dd19 |
233 | |
2c0cbef7 |
234 | =item B<excludes (@role_names)> |
235 | |
9e93dd19 |
236 | Roles can C<exclude> other roles, in effect saying "I can never be combined |
237 | with these C<@role_names>". This is a feature which should not be used |
85424612 |
238 | lightly. |
9e93dd19 |
239 | |
2c0cbef7 |
240 | =back |
241 | |
242 | =head1 CAVEATS |
243 | |
85424612 |
244 | Role support has only a few caveats: |
2c0cbef7 |
245 | |
246 | =over 4 |
76d37e5a |
247 | |
76d37e5a |
248 | =item * |
249 | |
85424612 |
250 | Roles cannot use the C<extends> keyword; it will throw an exception for now. |
76d37e5a |
251 | The same is true of the C<augment> and C<inner> keywords (not sure those |
252 | really make sense for roles). All other Moose keywords will be I<deferred> |
85424612 |
253 | so that they can be applied to the consuming class. |
76d37e5a |
254 | |
2c0cbef7 |
255 | =item * |
256 | |
85424612 |
257 | Role composition does its best to B<not> be order-sensitive when it comes to |
258 | conflict resolution and requirements detection. However, it is order-sensitive |
259 | when it comes to method modifiers. All before/around/after modifiers are |
260 | included whenever a role is composed into a class, and then applied in the order |
261 | in which the roles are used. This also means that there is no conflict for |
262 | before/around/after modifiers. |
2c0cbef7 |
263 | |
85424612 |
264 | In most cases, this will be a non-issue; however, it is something to keep in |
265 | mind when using method modifiers in a role. You should never assume any |
2c0cbef7 |
266 | ordering. |
267 | |
268 | =item * |
269 | |
270 | The C<requires> keyword currently only works with actual methods. A method |
271 | modifier (before/around/after and override) will not count as a fufillment |
272 | of the requirement, and neither will an autogenerated accessor for an attribute. |
273 | |
85424612 |
274 | It is likely that attribute accessors will eventually be allowed to fufill those |
275 | requirements, or we will introduce a C<requires_attr> keyword of some kind |
276 | instead. This decision has not yet been finalized. |
2c0cbef7 |
277 | |
e185c027 |
278 | =back |
279 | |
280 | =head1 BUGS |
281 | |
282 | All complex software has bugs lurking in it, and this module is no |
283 | exception. If you find a bug please either email me, or add the bug |
284 | to cpan-RT. |
285 | |
286 | =head1 AUTHOR |
287 | |
288 | Stevan Little E<lt>stevan@iinteractive.comE<gt> |
289 | |
db1ab48d |
290 | Christian Hansen E<lt>chansen@cpan.orgE<gt> |
98aae381 |
291 | |
e185c027 |
292 | =head1 COPYRIGHT AND LICENSE |
293 | |
b77fdbed |
294 | Copyright 2006, 2007 by Infinity Interactive, Inc. |
e185c027 |
295 | |
296 | L<http://www.iinteractive.com> |
297 | |
298 | This library is free software; you can redistribute it and/or modify |
299 | it under the same terms as Perl itself. |
300 | |
68117c45 |
301 | =cut |