Commit | Line | Data |
e185c027 |
1 | |
2 | package Moose::Role; |
3 | |
4 | use strict; |
5 | use warnings; |
6 | |
e65dccbc |
7 | use Scalar::Util 'blessed'; |
cc5e6b6f |
8 | use Carp 'confess', 'croak'; |
e185c027 |
9 | |
c4538447 |
10 | use Data::OptList; |
2d562421 |
11 | use Sub::Exporter; |
12 | |
19fabdd3 |
13 | our $VERSION = '0.52'; |
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 { |
685c7fac |
52 | croak "Roles do 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 (@) { |
cc5e6b6f |
64 | croak "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 (@) { |
cc5e6b6f |
71 | croak "Must specify at least one role" unless @_; |
d79e62fd |
72 | $meta->add_excluded_roles(@_); |
1b2aea39 |
73 | }); |
fb1e11d5 |
74 | }, |
2d562421 |
75 | has => sub { |
76 | my $meta = _find_meta(); |
1b2aea39 |
77 | return Class::MOP::subname('Moose::Role::has' => sub ($;%) { |
1580432f |
78 | my $name = shift; |
cc5e6b6f |
79 | croak 'Usage: has \'name\' => ( key => value, ... )' if @_ == 1; |
1580432f |
80 | my %options = @_; |
81 | my $attrs = ( ref($name) eq 'ARRAY' ) ? $name : [ ($name) ]; |
82 | $meta->add_attribute( $_, %options ) for @$attrs; |
1b2aea39 |
83 | }); |
fb1e11d5 |
84 | }, |
2d562421 |
85 | before => sub { |
86 | my $meta = _find_meta(); |
1b2aea39 |
87 | return Class::MOP::subname('Moose::Role::before' => sub (@&) { |
0558683c |
88 | my $code = pop @_; |
401cb5a6 |
89 | do { |
cc5e6b6f |
90 | croak "Moose::Role do not currently support " |
401cb5a6 |
91 | . ref($_) |
92 | . " references for before method modifiers" |
93 | if ref $_; |
94 | $meta->add_before_method_modifier($_, $code) |
95 | } for @_; |
1b2aea39 |
96 | }); |
fb1e11d5 |
97 | }, |
2d562421 |
98 | after => sub { |
99 | my $meta = _find_meta(); |
1b2aea39 |
100 | return Class::MOP::subname('Moose::Role::after' => sub (@&) { |
fb1e11d5 |
101 | my $code = pop @_; |
401cb5a6 |
102 | do { |
cc5e6b6f |
103 | croak "Moose::Role do not currently support " |
401cb5a6 |
104 | . ref($_) |
105 | . " references for after method modifiers" |
106 | if ref $_; |
107 | $meta->add_after_method_modifier($_, $code) |
108 | } for @_; |
1b2aea39 |
109 | }); |
fb1e11d5 |
110 | }, |
2d562421 |
111 | around => sub { |
112 | my $meta = _find_meta(); |
1b2aea39 |
113 | return Class::MOP::subname('Moose::Role::around' => sub (@&) { |
fb1e11d5 |
114 | my $code = pop @_; |
401cb5a6 |
115 | do { |
cc5e6b6f |
116 | croak "Moose::Role do not currently support " |
401cb5a6 |
117 | . ref($_) |
118 | . " references for around method modifiers" |
119 | if ref $_; |
120 | $meta->add_around_method_modifier($_, $code) |
121 | } for @_; |
1b2aea39 |
122 | }); |
fb1e11d5 |
123 | }, |
3f9e4b0a |
124 | # see Moose.pm for discussion |
fb1e11d5 |
125 | super => sub { |
401cb5a6 |
126 | return Class::MOP::subname('Moose::Role::super' => sub { |
127 | return unless $Moose::SUPER_BODY; $Moose::SUPER_BODY->(@Moose::SUPER_ARGS) |
128 | }); |
2d562421 |
129 | }, |
130 | override => sub { |
131 | my $meta = _find_meta(); |
1b2aea39 |
132 | return Class::MOP::subname('Moose::Role::override' => sub ($&) { |
0558683c |
133 | my ($name, $code) = @_; |
134 | $meta->add_override_method_modifier($name, $code); |
1b2aea39 |
135 | }); |
fb1e11d5 |
136 | }, |
2d562421 |
137 | inner => sub { |
138 | my $meta = _find_meta(); |
1b2aea39 |
139 | return Class::MOP::subname('Moose::Role::inner' => sub { |
cc5e6b6f |
140 | croak "Moose::Role cannot support 'inner'"; |
1b2aea39 |
141 | }); |
fb1e11d5 |
142 | }, |
2d562421 |
143 | augment => sub { |
144 | my $meta = _find_meta(); |
1b2aea39 |
145 | return Class::MOP::subname('Moose::Role::augment' => sub { |
cc5e6b6f |
146 | croak "Moose::Role cannot support 'augment'"; |
1b2aea39 |
147 | }); |
fb1e11d5 |
148 | }, |
2d562421 |
149 | confess => sub { |
150 | return \&Carp::confess; |
151 | }, |
152 | blessed => sub { |
153 | return \&Scalar::Util::blessed; |
fb1e11d5 |
154 | } |
155 | ); |
2d562421 |
156 | |
fb1e11d5 |
157 | my $exporter = Sub::Exporter::build_exporter({ |
2d562421 |
158 | exports => \%exports, |
159 | groups => { |
160 | default => [':all'] |
161 | } |
162 | }); |
fb1e11d5 |
163 | |
2d562421 |
164 | sub import { |
fc9a40d7 |
165 | $CALLER = |
166 | ref $_[1] && defined $_[1]->{into} ? $_[1]->{into} |
167 | : ref $_[1] |
168 | && defined $_[1]->{into_level} ? caller( $_[1]->{into_level} ) |
169 | : caller(); |
170 | |
86dd5d11 |
171 | # this works because both pragmas set $^H (see perldoc perlvar) |
172 | # which affects the current compilation - i.e. the file who use'd |
173 | # us - which is why we don't need to do anything special to make |
174 | # it affect that file rather than this one (which is already compiled) |
fb1e11d5 |
175 | |
c235cd98 |
176 | strict->import; |
fb1e11d5 |
177 | warnings->import; |
2d562421 |
178 | |
179 | # we should never export to main |
180 | return if $CALLER eq 'main'; |
181 | |
182 | goto $exporter; |
183 | }; |
184 | |
d31f9614 |
185 | sub unimport { |
186 | no strict 'refs'; |
fd75e12b |
187 | my $class = Moose::_get_caller(@_); |
d31f9614 |
188 | |
189 | # loop through the exports ... |
190 | foreach my $name ( keys %exports ) { |
191 | |
192 | # if we find one ... |
193 | if ( defined &{ $class . '::' . $name } ) { |
194 | my $keyword = \&{ $class . '::' . $name }; |
195 | |
196 | # make sure it is from Moose::Role |
197 | my ($pkg_name) = Class::MOP::get_code_info($keyword); |
198 | next if $pkg_name ne 'Moose::Role'; |
199 | |
200 | # and if it is from Moose::Role then undef the slot |
201 | delete ${ $class . '::' }{$name}; |
202 | } |
203 | } |
204 | } |
e185c027 |
205 | } |
206 | |
207 | 1; |
208 | |
209 | __END__ |
210 | |
211 | =pod |
212 | |
213 | =head1 NAME |
214 | |
215 | Moose::Role - The Moose Role |
216 | |
76d37e5a |
217 | =head1 SYNOPSIS |
218 | |
219 | package Eq; |
85424612 |
220 | use Moose::Role; # automatically turns on strict and warnings |
fb1e11d5 |
221 | |
e46edf94 |
222 | requires 'equal'; |
fb1e11d5 |
223 | |
224 | sub no_equal { |
76d37e5a |
225 | my ($self, $other) = @_; |
226 | !$self->equal($other); |
227 | } |
fb1e11d5 |
228 | |
76d37e5a |
229 | # ... then in your classes |
fb1e11d5 |
230 | |
76d37e5a |
231 | package Currency; |
85424612 |
232 | use Moose; # automatically turns on strict and warnings |
fb1e11d5 |
233 | |
76d37e5a |
234 | with 'Eq'; |
fb1e11d5 |
235 | |
76d37e5a |
236 | sub equal { |
237 | my ($self, $other) = @_; |
bdabd620 |
238 | $self->as_float == $other->as_float; |
76d37e5a |
239 | } |
240 | |
e185c027 |
241 | =head1 DESCRIPTION |
242 | |
85424612 |
243 | Role support in Moose is pretty solid at this point. However, the best |
244 | documentation is still the the test suite. It is fairly safe to assume Perl 6 |
245 | style behavior and then either refer to the test suite, or ask questions on |
246 | #moose if something doesn't quite do what you expect. |
d44714be |
247 | |
85424612 |
248 | We are planning writing some more documentation in the near future, but nothing |
249 | is ready yet, sorry. |
76d37e5a |
250 | |
2c0cbef7 |
251 | =head1 EXPORTED FUNCTIONS |
252 | |
85424612 |
253 | Moose::Role currently supports all of the functions that L<Moose> exports, but |
254 | differs slightly in how some items are handled (see L<CAVEATS> below for |
255 | details). |
76d37e5a |
256 | |
85424612 |
257 | Moose::Role also offers two role-specific keyword exports: |
e185c027 |
258 | |
259 | =over 4 |
260 | |
2c0cbef7 |
261 | =item B<requires (@method_names)> |
76d37e5a |
262 | |
fb1e11d5 |
263 | Roles can require that certain methods are implemented by any class which |
85424612 |
264 | C<does> the role. |
9e93dd19 |
265 | |
2c0cbef7 |
266 | =item B<excludes (@role_names)> |
267 | |
9e93dd19 |
268 | Roles can C<exclude> other roles, in effect saying "I can never be combined |
fb1e11d5 |
269 | with these C<@role_names>". This is a feature which should not be used |
85424612 |
270 | lightly. |
9e93dd19 |
271 | |
2c0cbef7 |
272 | =back |
273 | |
d31f9614 |
274 | =head2 B<unimport> |
275 | |
276 | Moose::Role offers a way to remove the keywords it exports, through the |
277 | C<unimport> method. You simply have to say C<no Moose::Role> at the bottom of |
278 | your code for this to work. |
279 | |
2c0cbef7 |
280 | =head1 CAVEATS |
281 | |
85424612 |
282 | Role support has only a few caveats: |
2c0cbef7 |
283 | |
284 | =over 4 |
76d37e5a |
285 | |
76d37e5a |
286 | =item * |
287 | |
fb1e11d5 |
288 | Roles cannot use the C<extends> keyword; it will throw an exception for now. |
289 | The same is true of the C<augment> and C<inner> keywords (not sure those |
290 | really make sense for roles). All other Moose keywords will be I<deferred> |
85424612 |
291 | so that they can be applied to the consuming class. |
76d37e5a |
292 | |
fb1e11d5 |
293 | =item * |
2c0cbef7 |
294 | |
85424612 |
295 | Role composition does its best to B<not> be order-sensitive when it comes to |
296 | conflict resolution and requirements detection. However, it is order-sensitive |
297 | when it comes to method modifiers. All before/around/after modifiers are |
298 | included whenever a role is composed into a class, and then applied in the order |
299 | in which the roles are used. This also means that there is no conflict for |
300 | before/around/after modifiers. |
2c0cbef7 |
301 | |
85424612 |
302 | In most cases, this will be a non-issue; however, it is something to keep in |
303 | mind when using method modifiers in a role. You should never assume any |
2c0cbef7 |
304 | ordering. |
305 | |
306 | =item * |
307 | |
fb1e11d5 |
308 | The C<requires> keyword currently only works with actual methods. A method |
309 | modifier (before/around/after and override) will not count as a fufillment |
2c0cbef7 |
310 | of the requirement, and neither will an autogenerated accessor for an attribute. |
311 | |
85424612 |
312 | It is likely that attribute accessors will eventually be allowed to fufill those |
313 | requirements, or we will introduce a C<requires_attr> keyword of some kind |
314 | instead. This decision has not yet been finalized. |
2c0cbef7 |
315 | |
e185c027 |
316 | =back |
317 | |
318 | =head1 BUGS |
319 | |
fb1e11d5 |
320 | All complex software has bugs lurking in it, and this module is no |
e185c027 |
321 | exception. If you find a bug please either email me, or add the bug |
322 | to cpan-RT. |
323 | |
324 | =head1 AUTHOR |
325 | |
326 | Stevan Little E<lt>stevan@iinteractive.comE<gt> |
327 | |
db1ab48d |
328 | Christian Hansen E<lt>chansen@cpan.orgE<gt> |
98aae381 |
329 | |
e185c027 |
330 | =head1 COPYRIGHT AND LICENSE |
331 | |
778db3ac |
332 | Copyright 2006-2008 by Infinity Interactive, Inc. |
e185c027 |
333 | |
334 | L<http://www.iinteractive.com> |
335 | |
336 | This library is free software; you can redistribute it and/or modify |
fb1e11d5 |
337 | it under the same terms as Perl itself. |
e185c027 |
338 | |
68117c45 |
339 | =cut |