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'; |
e185c027 |
9 | |
c4538447 |
10 | use Data::OptList; |
2d562421 |
11 | use Sub::Exporter; |
12 | |
1b2aea39 |
13 | our $VERSION = '0.09'; |
d44714be |
14 | our $AUTHORITY = 'cpan:STEVAN'; |
e185c027 |
15 | |
d7d8a8c7 |
16 | use Moose (); |
17 | use Moose::Util (); |
e65dccbc |
18 | |
e185c027 |
19 | use Moose::Meta::Role; |
7eaef7ad |
20 | use Moose::Util::TypeConstraints; |
e185c027 |
21 | |
2d562421 |
22 | { |
23 | my ( $CALLER, %METAS ); |
24 | |
25 | sub _find_meta { |
7eaef7ad |
26 | my $role = $CALLER; |
2d562421 |
27 | |
7eaef7ad |
28 | return $METAS{$role} if exists $METAS{$role}; |
fb1e11d5 |
29 | |
7eaef7ad |
30 | # make a subtype for each Moose class |
e324865b |
31 | role_type $role unless find_type_constraint($role); |
2d562421 |
32 | |
fb1e11d5 |
33 | my $meta; |
34 | if ($role->can('meta')) { |
35 | $meta = $role->meta(); |
36 | (blessed($meta) && $meta->isa('Moose::Meta::Role')) |
68efb014 |
37 | || confess "You already have a &meta function, but it does not return a Moose::Meta::Role"; |
fb1e11d5 |
38 | } |
39 | else { |
40 | $meta = Moose::Meta::Role->initialize($role); |
41 | $meta->alias_method('meta' => sub { $meta }); |
42 | } |
2d562421 |
43 | |
7eaef7ad |
44 | return $METAS{$role} = $meta; |
2d562421 |
45 | } |
fb1e11d5 |
46 | |
47 | |
48 | my %exports = ( |
2d562421 |
49 | extends => sub { |
50 | my $meta = _find_meta(); |
1b2aea39 |
51 | return Class::MOP::subname('Moose::Role::extends' => sub { |
2d562421 |
52 | confess "Moose::Role does not currently support 'extends'" |
1b2aea39 |
53 | }); |
fb1e11d5 |
54 | }, |
55 | with => sub { |
56 | my $meta = _find_meta(); |
1b2aea39 |
57 | return Class::MOP::subname('Moose::Role::with' => sub (@) { |
d7d8a8c7 |
58 | Moose::Util::apply_all_roles($meta, @_) |
1b2aea39 |
59 | }); |
fb1e11d5 |
60 | }, |
2d562421 |
61 | requires => sub { |
62 | my $meta = _find_meta(); |
1b2aea39 |
63 | return Class::MOP::subname('Moose::Role::requires' => sub (@) { |
68117c45 |
64 | confess "Must specify at least one method" unless @_; |
2d562421 |
65 | $meta->add_required_methods(@_); |
1b2aea39 |
66 | }); |
fb1e11d5 |
67 | }, |
d79e62fd |
68 | excludes => sub { |
69 | my $meta = _find_meta(); |
1b2aea39 |
70 | return Class::MOP::subname('Moose::Role::excludes' => sub (@) { |
68117c45 |
71 | confess "Must specify at least one role" unless @_; |
d79e62fd |
72 | $meta->add_excluded_roles(@_); |
1b2aea39 |
73 | }); |
fb1e11d5 |
74 | }, |
2d562421 |
75 | has => sub { |
76 | my $meta = _find_meta(); |
1b2aea39 |
77 | return Class::MOP::subname('Moose::Role::has' => sub ($;%) { |
fb1e11d5 |
78 | my ($name, %options) = @_; |
79 | $meta->add_attribute($name, %options) |
1b2aea39 |
80 | }); |
fb1e11d5 |
81 | }, |
2d562421 |
82 | before => sub { |
83 | my $meta = _find_meta(); |
1b2aea39 |
84 | return Class::MOP::subname('Moose::Role::before' => sub (@&) { |
0558683c |
85 | my $code = pop @_; |
86 | $meta->add_before_method_modifier($_, $code) for @_; |
1b2aea39 |
87 | }); |
fb1e11d5 |
88 | }, |
2d562421 |
89 | after => sub { |
90 | my $meta = _find_meta(); |
1b2aea39 |
91 | return Class::MOP::subname('Moose::Role::after' => sub (@&) { |
fb1e11d5 |
92 | my $code = pop @_; |
93 | $meta->add_after_method_modifier($_, $code) for @_; |
1b2aea39 |
94 | }); |
fb1e11d5 |
95 | }, |
2d562421 |
96 | around => sub { |
97 | my $meta = _find_meta(); |
1b2aea39 |
98 | return Class::MOP::subname('Moose::Role::around' => sub (@&) { |
fb1e11d5 |
99 | my $code = pop @_; |
100 | $meta->add_around_method_modifier($_, $code) for @_; |
1b2aea39 |
101 | }); |
fb1e11d5 |
102 | }, |
3f9e4b0a |
103 | # see Moose.pm for discussion |
fb1e11d5 |
104 | super => sub { |
1b2aea39 |
105 | return Class::MOP::subname('Moose::Role::super' => sub { return unless $Moose::SUPER_BODY; $Moose::SUPER_BODY->(@Moose::SUPER_ARGS) }) |
2d562421 |
106 | }, |
3f9e4b0a |
107 | #next => sub { |
108 | # return subname 'Moose::Role::next' => sub { @_ = @Moose::SUPER_ARGS; goto \&next::method }; |
109 | #}, |
2d562421 |
110 | override => sub { |
111 | my $meta = _find_meta(); |
1b2aea39 |
112 | return Class::MOP::subname('Moose::Role::override' => sub ($&) { |
0558683c |
113 | my ($name, $code) = @_; |
114 | $meta->add_override_method_modifier($name, $code); |
1b2aea39 |
115 | }); |
fb1e11d5 |
116 | }, |
2d562421 |
117 | inner => sub { |
118 | my $meta = _find_meta(); |
1b2aea39 |
119 | return Class::MOP::subname('Moose::Role::inner' => sub { |
0558683c |
120 | confess "Moose::Role cannot support 'inner'"; |
1b2aea39 |
121 | }); |
fb1e11d5 |
122 | }, |
2d562421 |
123 | augment => sub { |
124 | my $meta = _find_meta(); |
1b2aea39 |
125 | return Class::MOP::subname('Moose::Role::augment' => sub { |
06b30515 |
126 | confess "Moose::Role cannot support 'augment'"; |
1b2aea39 |
127 | }); |
fb1e11d5 |
128 | }, |
2d562421 |
129 | confess => sub { |
130 | return \&Carp::confess; |
131 | }, |
132 | blessed => sub { |
133 | return \&Scalar::Util::blessed; |
fb1e11d5 |
134 | } |
135 | ); |
2d562421 |
136 | |
fb1e11d5 |
137 | my $exporter = Sub::Exporter::build_exporter({ |
2d562421 |
138 | exports => \%exports, |
139 | groups => { |
140 | default => [':all'] |
141 | } |
142 | }); |
fb1e11d5 |
143 | |
2d562421 |
144 | sub import { |
fc9a40d7 |
145 | $CALLER = |
146 | ref $_[1] && defined $_[1]->{into} ? $_[1]->{into} |
147 | : ref $_[1] |
148 | && defined $_[1]->{into_level} ? caller( $_[1]->{into_level} ) |
149 | : caller(); |
150 | |
86dd5d11 |
151 | # this works because both pragmas set $^H (see perldoc perlvar) |
152 | # which affects the current compilation - i.e. the file who use'd |
153 | # us - which is why we don't need to do anything special to make |
154 | # it affect that file rather than this one (which is already compiled) |
fb1e11d5 |
155 | |
c235cd98 |
156 | strict->import; |
fb1e11d5 |
157 | warnings->import; |
2d562421 |
158 | |
159 | # we should never export to main |
160 | return if $CALLER eq 'main'; |
161 | |
162 | goto $exporter; |
163 | }; |
164 | |
e185c027 |
165 | } |
166 | |
167 | 1; |
168 | |
169 | __END__ |
170 | |
171 | =pod |
172 | |
173 | =head1 NAME |
174 | |
175 | Moose::Role - The Moose Role |
176 | |
76d37e5a |
177 | =head1 SYNOPSIS |
178 | |
179 | package Eq; |
85424612 |
180 | use Moose::Role; # automatically turns on strict and warnings |
fb1e11d5 |
181 | |
e46edf94 |
182 | requires 'equal'; |
fb1e11d5 |
183 | |
184 | sub no_equal { |
76d37e5a |
185 | my ($self, $other) = @_; |
186 | !$self->equal($other); |
187 | } |
fb1e11d5 |
188 | |
76d37e5a |
189 | # ... then in your classes |
fb1e11d5 |
190 | |
76d37e5a |
191 | package Currency; |
85424612 |
192 | use Moose; # automatically turns on strict and warnings |
fb1e11d5 |
193 | |
76d37e5a |
194 | with 'Eq'; |
fb1e11d5 |
195 | |
76d37e5a |
196 | sub equal { |
197 | my ($self, $other) = @_; |
bdabd620 |
198 | $self->as_float == $other->as_float; |
76d37e5a |
199 | } |
200 | |
e185c027 |
201 | =head1 DESCRIPTION |
202 | |
85424612 |
203 | Role support in Moose is pretty solid at this point. However, the best |
204 | documentation is still the the test suite. It is fairly safe to assume Perl 6 |
205 | style behavior and then either refer to the test suite, or ask questions on |
206 | #moose if something doesn't quite do what you expect. |
d44714be |
207 | |
85424612 |
208 | We are planning writing some more documentation in the near future, but nothing |
209 | is ready yet, sorry. |
76d37e5a |
210 | |
2c0cbef7 |
211 | =head1 EXPORTED FUNCTIONS |
212 | |
85424612 |
213 | Moose::Role currently supports all of the functions that L<Moose> exports, but |
214 | differs slightly in how some items are handled (see L<CAVEATS> below for |
215 | details). |
76d37e5a |
216 | |
85424612 |
217 | Moose::Role also offers two role-specific keyword exports: |
e185c027 |
218 | |
219 | =over 4 |
220 | |
2c0cbef7 |
221 | =item B<requires (@method_names)> |
76d37e5a |
222 | |
fb1e11d5 |
223 | Roles can require that certain methods are implemented by any class which |
85424612 |
224 | C<does> the role. |
9e93dd19 |
225 | |
2c0cbef7 |
226 | =item B<excludes (@role_names)> |
227 | |
9e93dd19 |
228 | Roles can C<exclude> other roles, in effect saying "I can never be combined |
fb1e11d5 |
229 | with these C<@role_names>". This is a feature which should not be used |
85424612 |
230 | lightly. |
9e93dd19 |
231 | |
2c0cbef7 |
232 | =back |
233 | |
234 | =head1 CAVEATS |
235 | |
85424612 |
236 | Role support has only a few caveats: |
2c0cbef7 |
237 | |
238 | =over 4 |
76d37e5a |
239 | |
76d37e5a |
240 | =item * |
241 | |
fb1e11d5 |
242 | Roles cannot use the C<extends> keyword; it will throw an exception for now. |
243 | The same is true of the C<augment> and C<inner> keywords (not sure those |
244 | really make sense for roles). All other Moose keywords will be I<deferred> |
85424612 |
245 | so that they can be applied to the consuming class. |
76d37e5a |
246 | |
fb1e11d5 |
247 | =item * |
2c0cbef7 |
248 | |
85424612 |
249 | Role composition does its best to B<not> be order-sensitive when it comes to |
250 | conflict resolution and requirements detection. However, it is order-sensitive |
251 | when it comes to method modifiers. All before/around/after modifiers are |
252 | included whenever a role is composed into a class, and then applied in the order |
253 | in which the roles are used. This also means that there is no conflict for |
254 | before/around/after modifiers. |
2c0cbef7 |
255 | |
85424612 |
256 | In most cases, this will be a non-issue; however, it is something to keep in |
257 | mind when using method modifiers in a role. You should never assume any |
2c0cbef7 |
258 | ordering. |
259 | |
260 | =item * |
261 | |
fb1e11d5 |
262 | The C<requires> keyword currently only works with actual methods. A method |
263 | modifier (before/around/after and override) will not count as a fufillment |
2c0cbef7 |
264 | of the requirement, and neither will an autogenerated accessor for an attribute. |
265 | |
85424612 |
266 | It is likely that attribute accessors will eventually be allowed to fufill those |
267 | requirements, or we will introduce a C<requires_attr> keyword of some kind |
268 | instead. This decision has not yet been finalized. |
2c0cbef7 |
269 | |
e185c027 |
270 | =back |
271 | |
272 | =head1 BUGS |
273 | |
fb1e11d5 |
274 | All complex software has bugs lurking in it, and this module is no |
e185c027 |
275 | exception. If you find a bug please either email me, or add the bug |
276 | to cpan-RT. |
277 | |
278 | =head1 AUTHOR |
279 | |
280 | Stevan Little E<lt>stevan@iinteractive.comE<gt> |
281 | |
db1ab48d |
282 | Christian Hansen E<lt>chansen@cpan.orgE<gt> |
98aae381 |
283 | |
e185c027 |
284 | =head1 COPYRIGHT AND LICENSE |
285 | |
778db3ac |
286 | Copyright 2006-2008 by Infinity Interactive, Inc. |
e185c027 |
287 | |
288 | L<http://www.iinteractive.com> |
289 | |
290 | This library is free software; you can redistribute it and/or modify |
fb1e11d5 |
291 | it under the same terms as Perl itself. |
e185c027 |
292 | |
68117c45 |
293 | =cut |