Commit | Line | Data |
94b19069 |
1 | |
2 | package Class::MOP; |
3 | |
4 | use strict; |
5 | use warnings; |
6 | |
3cf322a0 |
7 | use MRO::Compat; |
8 | |
4c105333 |
9 | use Carp 'confess'; |
10 | use Scalar::Util 'weaken'; |
8b978dd5 |
11 | |
0531f510 |
12 | use Sub::Identify 'get_code_info'; |
13 | |
fc4f8f91 |
14 | BEGIN { |
15 | local $@; |
16 | eval { |
17 | require Sub::Name; |
18 | Sub::Name->import(qw(subname)); |
19 | 1 |
20 | } or eval 'sub subname { $_[1] }'; |
21 | |
22 | # this is either part of core or set up appropriately by MRO::Compat |
23 | *check_package_cache_flag = \&mro::get_pkg_gen; |
712ecd18 |
24 | |
25 | eval { |
26 | require Devel::GlobalDestruction; |
27 | Devel::GlobalDestruction->import("in_global_destruction"); |
28 | 1; |
29 | } or *in_global_destruction = sub () { '' }; |
fc4f8f91 |
30 | } |
31 | |
32 | |
0531f510 |
33 | use Class::MOP::Class; |
34 | use Class::MOP::Attribute; |
35 | use Class::MOP::Method; |
36 | |
37 | use Class::MOP::Immutable; |
38 | |
b1f5f41d |
39 | BEGIN { |
11b56828 |
40 | *IS_RUNNING_ON_5_10 = ($] < 5.009_005) |
41 | ? sub () { 0 } |
4c105333 |
42 | : sub () { 1 }; |
46b23b44 |
43 | |
9efe16ca |
44 | *HAVE_ISAREV = defined(&mro::get_isarev) |
45 | ? sub () { 1 } |
46 | : sub () { 1 }; |
b1f5f41d |
47 | } |
e0e4674a |
48 | |
fc4f8f91 |
49 | our $VERSION = '0.65'; |
50 | our $AUTHORITY = 'cpan:STEVAN'; |
51 | |
0531f510 |
52 | # after that everything is loaded, if we're allowed try to load faster XS |
53 | # versions of various things |
54 | unless ($ENV{CLASS_MOP_NO_XS}) { |
55 | my $e = do { |
56 | local $@; |
57 | eval { |
58 | require XSLoader; |
fc4f8f91 |
59 | __PACKAGE__->XSLoader::load($VERSION); |
0531f510 |
60 | }; |
61 | $@; |
62 | }; |
15273f3c |
63 | |
0531f510 |
64 | die $e if $e && $e !~ /object version|loadable object/; |
65 | } |
15273f3c |
66 | |
be7677c7 |
67 | { |
68 | # Metaclasses are singletons, so we cache them here. |
69 | # there is no need to worry about destruction though |
70 | # because they should die only when the program dies. |
71 | # After all, do package definitions even get reaped? |
1d68af04 |
72 | my %METAS; |
73 | |
74 | # means of accessing all the metaclasses that have |
be7677c7 |
75 | # been initialized thus far (for mugwumps obj browser) |
1d68af04 |
76 | sub get_all_metaclasses { %METAS } |
77 | sub get_all_metaclass_instances { values %METAS } |
78 | sub get_all_metaclass_names { keys %METAS } |
be7677c7 |
79 | sub get_metaclass_by_name { $METAS{$_[0]} } |
1d68af04 |
80 | sub store_metaclass_by_name { $METAS{$_[0]} = $_[1] } |
81 | sub weaken_metaclass { weaken($METAS{$_[0]}) } |
be7677c7 |
82 | sub does_metaclass_exist { exists $METAS{$_[0]} && defined $METAS{$_[0]} } |
1d68af04 |
83 | sub remove_metaclass_by_name { $METAS{$_[0]} = undef } |
84 | |
be7677c7 |
85 | # NOTE: |
1d68af04 |
86 | # We only cache metaclasses, meaning instances of |
87 | # Class::MOP::Class. We do not cache instance of |
be7677c7 |
88 | # Class::MOP::Package or Class::MOP::Module. Mostly |
1d68af04 |
89 | # because I don't yet see a good reason to do so. |
be7677c7 |
90 | } |
91 | |
448b6e55 |
92 | sub load_class { |
93 | my $class = shift; |
ab5e2f48 |
94 | |
95 | if (ref($class) || !defined($class) || !length($class)) { |
96 | my $display = defined($class) ? $class : 'undef'; |
97 | confess "Invalid class name ($display)"; |
98 | } |
99 | |
07940968 |
100 | # if the class is not already loaded in the symbol table.. |
101 | unless (is_class_loaded($class)) { |
102 | # require it |
103 | my $file = $class . '.pm'; |
104 | $file =~ s{::}{/}g; |
1b8d9282 |
105 | my $e = do { local $@; eval { require($file) }; $@ }; |
106 | confess "Could not load class ($class) because : $e" if $e; |
07940968 |
107 | } |
108 | |
109 | # initialize a metaclass if necessary |
448b6e55 |
110 | unless (does_metaclass_exist($class)) { |
1b8d9282 |
111 | my $e = do { local $@; eval { Class::MOP::Class->initialize($class) }; $@ }; |
112 | confess "Could not initialize class ($class) because : $e" if $e; |
448b6e55 |
113 | } |
07940968 |
114 | |
1b8d9282 |
115 | return get_metaclass_by_name($class) if defined wantarray; |
448b6e55 |
116 | } |
117 | |
118 | sub is_class_loaded { |
c1d5345a |
119 | my $class = shift; |
26fcef27 |
120 | |
121 | return 0 if ref($class) || !defined($class) || !length($class); |
122 | |
123 | # walk the symbol table tree to avoid autovififying |
124 | # \*{${main::}{"Foo::"}} == \*main::Foo:: |
125 | |
126 | my $pack = \*::; |
127 | foreach my $part (split('::', $class)) { |
128 | return 0 unless exists ${$$pack}{"${part}::"}; |
129 | $pack = \*{${$$pack}{"${part}::"}}; |
c1d5345a |
130 | } |
26fcef27 |
131 | |
132 | # check for $VERSION or @ISA |
133 | return 1 if exists ${$$pack}{VERSION} |
134 | && defined *{${$$pack}{VERSION}}{SCALAR}; |
135 | return 1 if exists ${$$pack}{ISA} |
136 | && defined *{${$$pack}{ISA}}{ARRAY}; |
137 | |
138 | # check for any method |
139 | foreach ( keys %{$$pack} ) { |
140 | next if substr($_, -2, 2) eq '::'; |
d5be3722 |
141 | |
142 | my $glob = ${$$pack}{$_} || next; |
143 | |
9e275e86 |
144 | # constant subs |
d5be3722 |
145 | if ( IS_RUNNING_ON_5_10 ) { |
146 | return 1 if ref $glob eq 'SCALAR'; |
147 | } |
148 | |
149 | return 1 if defined *{$glob}{CODE}; |
26fcef27 |
150 | } |
151 | |
152 | # fail |
c1d5345a |
153 | return 0; |
448b6e55 |
154 | } |
155 | |
156 | |
aa448b16 |
157 | ## ---------------------------------------------------------------------------- |
158 | ## Setting up our environment ... |
159 | ## ---------------------------------------------------------------------------- |
1d68af04 |
160 | ## Class::MOP needs to have a few things in the global perl environment so |
aa448b16 |
161 | ## that it can operate effectively. Those things are done here. |
162 | ## ---------------------------------------------------------------------------- |
163 | |
3bf7644b |
164 | # ... nothing yet actually ;) |
8b978dd5 |
165 | |
b51af7f9 |
166 | ## ---------------------------------------------------------------------------- |
1d68af04 |
167 | ## Bootstrapping |
b51af7f9 |
168 | ## ---------------------------------------------------------------------------- |
1d68af04 |
169 | ## The code below here is to bootstrap our MOP with itself. This is also |
b51af7f9 |
170 | ## sometimes called "tying the knot". By doing this, we make it much easier |
171 | ## to extend the MOP through subclassing and such since now you can use the |
1d68af04 |
172 | ## MOP itself to extend itself. |
173 | ## |
b51af7f9 |
174 | ## Yes, I know, thats weird and insane, but it's a good thing, trust me :) |
1d68af04 |
175 | ## ---------------------------------------------------------------------------- |
727919c5 |
176 | |
1d68af04 |
177 | # We need to add in the meta-attributes here so that |
178 | # any subclass of Class::MOP::* will be able to |
727919c5 |
179 | # inherit them using &construct_instance |
180 | |
f0480c45 |
181 | ## -------------------------------------------------------- |
6d5355c3 |
182 | ## Class::MOP::Package |
727919c5 |
183 | |
6d5355c3 |
184 | Class::MOP::Package->meta->add_attribute( |
8683db0e |
185 | Class::MOP::Attribute->new('package' => ( |
b880e0de |
186 | reader => { |
1d68af04 |
187 | # NOTE: we need to do this in order |
188 | # for the instance meta-object to |
b880e0de |
189 | # not fall into meta-circular death |
1d68af04 |
190 | # |
ce2ae40f |
191 | # we just alias the original method |
1d68af04 |
192 | # rather than re-produce it here |
ce2ae40f |
193 | 'name' => \&Class::MOP::Package::name |
b880e0de |
194 | }, |
727919c5 |
195 | )) |
196 | ); |
197 | |
a5e51f0b |
198 | Class::MOP::Package->meta->add_attribute( |
8683db0e |
199 | Class::MOP::Attribute->new('namespace' => ( |
a5e51f0b |
200 | reader => { |
56dcfc1a |
201 | # NOTE: |
ce2ae40f |
202 | # we just alias the original method |
203 | # rather than re-produce it here |
204 | 'namespace' => \&Class::MOP::Package::namespace |
a5e51f0b |
205 | }, |
2e877f58 |
206 | init_arg => undef, |
c4260b45 |
207 | default => sub { \undef } |
a5e51f0b |
208 | )) |
209 | ); |
210 | |
9d6dce77 |
211 | # NOTE: |
212 | # use the metaclass to construct the meta-package |
213 | # which is a superclass of the metaclass itself :P |
214 | Class::MOP::Package->meta->add_method('initialize' => sub { |
215 | my $class = shift; |
216 | my $package_name = shift; |
1d68af04 |
217 | $class->meta->new_object('package' => $package_name, @_); |
9d6dce77 |
218 | }); |
219 | |
f0480c45 |
220 | ## -------------------------------------------------------- |
221 | ## Class::MOP::Module |
222 | |
223 | # NOTE: |
1d68af04 |
224 | # yeah this is kind of stretching things a bit, |
f0480c45 |
225 | # but truthfully the version should be an attribute |
1d68af04 |
226 | # of the Module, the weirdness comes from having to |
227 | # stick to Perl 5 convention and store it in the |
228 | # $VERSION package variable. Basically if you just |
229 | # squint at it, it will look how you want it to look. |
f0480c45 |
230 | # Either as a package variable, or as a attribute of |
231 | # the metaclass, isn't abstraction great :) |
232 | |
233 | Class::MOP::Module->meta->add_attribute( |
8683db0e |
234 | Class::MOP::Attribute->new('version' => ( |
f0480c45 |
235 | reader => { |
ce2ae40f |
236 | # NOTE: |
237 | # we just alias the original method |
1d68af04 |
238 | # rather than re-produce it here |
ce2ae40f |
239 | 'version' => \&Class::MOP::Module::version |
f0480c45 |
240 | }, |
2e877f58 |
241 | init_arg => undef, |
c4260b45 |
242 | default => sub { \undef } |
f0480c45 |
243 | )) |
244 | ); |
245 | |
246 | # NOTE: |
1d68af04 |
247 | # By following the same conventions as version here, |
248 | # we are opening up the possibility that people can |
249 | # use the $AUTHORITY in non-Class::MOP modules as |
250 | # well. |
f0480c45 |
251 | |
252 | Class::MOP::Module->meta->add_attribute( |
8683db0e |
253 | Class::MOP::Attribute->new('authority' => ( |
f0480c45 |
254 | reader => { |
ce2ae40f |
255 | # NOTE: |
256 | # we just alias the original method |
1d68af04 |
257 | # rather than re-produce it here |
ce2ae40f |
258 | 'authority' => \&Class::MOP::Module::authority |
1d68af04 |
259 | }, |
2e877f58 |
260 | init_arg => undef, |
c4260b45 |
261 | default => sub { \undef } |
f0480c45 |
262 | )) |
263 | ); |
264 | |
265 | ## -------------------------------------------------------- |
6d5355c3 |
266 | ## Class::MOP::Class |
267 | |
727919c5 |
268 | Class::MOP::Class->meta->add_attribute( |
8683db0e |
269 | Class::MOP::Attribute->new('attributes' => ( |
f7259199 |
270 | reader => { |
1d68af04 |
271 | # NOTE: we need to do this in order |
272 | # for the instance meta-object to |
273 | # not fall into meta-circular death |
274 | # |
ce2ae40f |
275 | # we just alias the original method |
1d68af04 |
276 | # rather than re-produce it here |
ce2ae40f |
277 | 'get_attribute_map' => \&Class::MOP::Class::get_attribute_map |
f7259199 |
278 | }, |
727919c5 |
279 | default => sub { {} } |
280 | )) |
281 | ); |
282 | |
351bd7d4 |
283 | Class::MOP::Class->meta->add_attribute( |
8683db0e |
284 | Class::MOP::Attribute->new('methods' => ( |
1d68af04 |
285 | reader => { |
ce2ae40f |
286 | # NOTE: |
287 | # we just alias the original method |
1d68af04 |
288 | # rather than re-produce it here |
ce2ae40f |
289 | 'get_method_map' => \&Class::MOP::Class::get_method_map |
92330ee2 |
290 | }, |
7855ddba |
291 | default => sub { {} } |
c4260b45 |
292 | )) |
293 | ); |
294 | |
295 | Class::MOP::Class->meta->add_attribute( |
8683db0e |
296 | Class::MOP::Attribute->new('superclasses' => ( |
c23184fc |
297 | accessor => { |
298 | # NOTE: |
299 | # we just alias the original method |
1d68af04 |
300 | # rather than re-produce it here |
c23184fc |
301 | 'superclasses' => \&Class::MOP::Class::superclasses |
302 | }, |
2e877f58 |
303 | init_arg => undef, |
c23184fc |
304 | default => sub { \undef } |
305 | )) |
306 | ); |
307 | |
308 | Class::MOP::Class->meta->add_attribute( |
8683db0e |
309 | Class::MOP::Attribute->new('attribute_metaclass' => ( |
1d68af04 |
310 | reader => { |
6d2118a4 |
311 | # NOTE: |
312 | # we just alias the original method |
1d68af04 |
313 | # rather than re-produce it here |
6d2118a4 |
314 | 'attribute_metaclass' => \&Class::MOP::Class::attribute_metaclass |
1d68af04 |
315 | }, |
351bd7d4 |
316 | default => 'Class::MOP::Attribute', |
317 | )) |
318 | ); |
319 | |
320 | Class::MOP::Class->meta->add_attribute( |
8683db0e |
321 | Class::MOP::Attribute->new('method_metaclass' => ( |
1d68af04 |
322 | reader => { |
6d2118a4 |
323 | # NOTE: |
324 | # we just alias the original method |
1d68af04 |
325 | # rather than re-produce it here |
6d2118a4 |
326 | 'method_metaclass' => \&Class::MOP::Class::method_metaclass |
327 | }, |
1d68af04 |
328 | default => 'Class::MOP::Method', |
351bd7d4 |
329 | )) |
330 | ); |
331 | |
2bab2be6 |
332 | Class::MOP::Class->meta->add_attribute( |
8683db0e |
333 | Class::MOP::Attribute->new('instance_metaclass' => ( |
b880e0de |
334 | reader => { |
1d68af04 |
335 | # NOTE: we need to do this in order |
336 | # for the instance meta-object to |
337 | # not fall into meta-circular death |
338 | # |
ce2ae40f |
339 | # we just alias the original method |
1d68af04 |
340 | # rather than re-produce it here |
ce2ae40f |
341 | 'instance_metaclass' => \&Class::MOP::Class::instance_metaclass |
b880e0de |
342 | }, |
1d68af04 |
343 | default => 'Class::MOP::Instance', |
2bab2be6 |
344 | )) |
345 | ); |
346 | |
9d6dce77 |
347 | # NOTE: |
1d68af04 |
348 | # we don't actually need to tie the knot with |
349 | # Class::MOP::Class here, it is actually handled |
350 | # within Class::MOP::Class itself in the |
351 | # construct_class_instance method. |
9d6dce77 |
352 | |
f0480c45 |
353 | ## -------------------------------------------------------- |
727919c5 |
354 | ## Class::MOP::Attribute |
355 | |
7b31baf4 |
356 | Class::MOP::Attribute->meta->add_attribute( |
8683db0e |
357 | Class::MOP::Attribute->new('name' => ( |
c23184fc |
358 | reader => { |
1d68af04 |
359 | # NOTE: we need to do this in order |
360 | # for the instance meta-object to |
361 | # not fall into meta-circular death |
362 | # |
ce2ae40f |
363 | # we just alias the original method |
1d68af04 |
364 | # rather than re-produce it here |
ce2ae40f |
365 | 'name' => \&Class::MOP::Attribute::name |
b880e0de |
366 | } |
7b31baf4 |
367 | )) |
368 | ); |
369 | |
370 | Class::MOP::Attribute->meta->add_attribute( |
8683db0e |
371 | Class::MOP::Attribute->new('associated_class' => ( |
c23184fc |
372 | reader => { |
1d68af04 |
373 | # NOTE: we need to do this in order |
374 | # for the instance meta-object to |
375 | # not fall into meta-circular death |
376 | # |
ce2ae40f |
377 | # we just alias the original method |
1d68af04 |
378 | # rather than re-produce it here |
ce2ae40f |
379 | 'associated_class' => \&Class::MOP::Attribute::associated_class |
b880e0de |
380 | } |
7b31baf4 |
381 | )) |
382 | ); |
383 | |
384 | Class::MOP::Attribute->meta->add_attribute( |
8683db0e |
385 | Class::MOP::Attribute->new('accessor' => ( |
6d2118a4 |
386 | reader => { 'accessor' => \&Class::MOP::Attribute::accessor }, |
387 | predicate => { 'has_accessor' => \&Class::MOP::Attribute::has_accessor }, |
7b31baf4 |
388 | )) |
389 | ); |
390 | |
391 | Class::MOP::Attribute->meta->add_attribute( |
8683db0e |
392 | Class::MOP::Attribute->new('reader' => ( |
6d2118a4 |
393 | reader => { 'reader' => \&Class::MOP::Attribute::reader }, |
394 | predicate => { 'has_reader' => \&Class::MOP::Attribute::has_reader }, |
7b31baf4 |
395 | )) |
396 | ); |
397 | |
398 | Class::MOP::Attribute->meta->add_attribute( |
8683db0e |
399 | Class::MOP::Attribute->new('initializer' => ( |
8ee74136 |
400 | reader => { 'initializer' => \&Class::MOP::Attribute::initializer }, |
401 | predicate => { 'has_initializer' => \&Class::MOP::Attribute::has_initializer }, |
0ab65f99 |
402 | )) |
403 | ); |
404 | |
405 | Class::MOP::Attribute->meta->add_attribute( |
8683db0e |
406 | Class::MOP::Attribute->new('writer' => ( |
6d2118a4 |
407 | reader => { 'writer' => \&Class::MOP::Attribute::writer }, |
408 | predicate => { 'has_writer' => \&Class::MOP::Attribute::has_writer }, |
7b31baf4 |
409 | )) |
410 | ); |
411 | |
412 | Class::MOP::Attribute->meta->add_attribute( |
8683db0e |
413 | Class::MOP::Attribute->new('predicate' => ( |
6d2118a4 |
414 | reader => { 'predicate' => \&Class::MOP::Attribute::predicate }, |
415 | predicate => { 'has_predicate' => \&Class::MOP::Attribute::has_predicate }, |
7b31baf4 |
416 | )) |
417 | ); |
418 | |
419 | Class::MOP::Attribute->meta->add_attribute( |
8683db0e |
420 | Class::MOP::Attribute->new('clearer' => ( |
6d2118a4 |
421 | reader => { 'clearer' => \&Class::MOP::Attribute::clearer }, |
422 | predicate => { 'has_clearer' => \&Class::MOP::Attribute::has_clearer }, |
7d28758b |
423 | )) |
424 | ); |
425 | |
426 | Class::MOP::Attribute->meta->add_attribute( |
8683db0e |
427 | Class::MOP::Attribute->new('builder' => ( |
1d68af04 |
428 | reader => { 'builder' => \&Class::MOP::Attribute::builder }, |
429 | predicate => { 'has_builder' => \&Class::MOP::Attribute::has_builder }, |
430 | )) |
431 | ); |
432 | |
433 | Class::MOP::Attribute->meta->add_attribute( |
8683db0e |
434 | Class::MOP::Attribute->new('init_arg' => ( |
6d2118a4 |
435 | reader => { 'init_arg' => \&Class::MOP::Attribute::init_arg }, |
436 | predicate => { 'has_init_arg' => \&Class::MOP::Attribute::has_init_arg }, |
7b31baf4 |
437 | )) |
438 | ); |
439 | |
440 | Class::MOP::Attribute->meta->add_attribute( |
8683db0e |
441 | Class::MOP::Attribute->new('default' => ( |
7b31baf4 |
442 | # default has a custom 'reader' method ... |
1d68af04 |
443 | predicate => { 'has_default' => \&Class::MOP::Attribute::has_default }, |
7b31baf4 |
444 | )) |
445 | ); |
446 | |
3545c727 |
447 | Class::MOP::Attribute->meta->add_attribute( |
8683db0e |
448 | Class::MOP::Attribute->new('associated_methods' => ( |
c23184fc |
449 | reader => { 'associated_methods' => \&Class::MOP::Attribute::associated_methods }, |
1d68af04 |
450 | default => sub { [] } |
3545c727 |
451 | )) |
452 | ); |
727919c5 |
453 | |
454 | # NOTE: (meta-circularity) |
455 | # This should be one of the last things done |
456 | # it will "tie the knot" with Class::MOP::Attribute |
1d68af04 |
457 | # so that it uses the attributes meta-objects |
458 | # to construct itself. |
727919c5 |
459 | Class::MOP::Attribute->meta->add_method('new' => sub { |
649efb63 |
460 | my ( $class, @args ) = @_; |
461 | |
462 | unshift @args, "name" if @args % 2 == 1; |
463 | my %options = @args; |
464 | |
465 | my $name = $options{name}; |
1d68af04 |
466 | |
727919c5 |
467 | (defined $name && $name) |
468 | || confess "You must provide a name for the attribute"; |
1d68af04 |
469 | $options{init_arg} = $name |
5659d76e |
470 | if not exists $options{init_arg}; |
1d68af04 |
471 | |
472 | if(exists $options{builder}){ |
473 | confess("builder must be a defined scalar value which is a method name") |
474 | if ref $options{builder} || !(defined $options{builder}); |
475 | confess("Setting both default and builder is not allowed.") |
476 | if exists $options{default}; |
8fe581e5 |
477 | } else { |
478 | (Class::MOP::Attribute::is_default_a_coderef(\%options)) |
479 | || confess("References are not allowed as default values, you must ". |
3c0a8087 |
480 | "wrap the default of '$name' in a CODE reference (ex: sub { [] } and not [])") |
8fe581e5 |
481 | if exists $options{default} && ref $options{default}; |
1d68af04 |
482 | } |
8683db0e |
483 | |
5659d76e |
484 | # return the new object |
649efb63 |
485 | $class->meta->new_object(%options); |
5659d76e |
486 | }); |
487 | |
488 | Class::MOP::Attribute->meta->add_method('clone' => sub { |
a740253a |
489 | my $self = shift; |
1d68af04 |
490 | $self->meta->clone_object($self, @_); |
727919c5 |
491 | }); |
492 | |
f0480c45 |
493 | ## -------------------------------------------------------- |
b6164407 |
494 | ## Class::MOP::Method |
b6164407 |
495 | Class::MOP::Method->meta->add_attribute( |
8683db0e |
496 | Class::MOP::Attribute->new('body' => ( |
c23184fc |
497 | reader => { 'body' => \&Class::MOP::Method::body }, |
b6164407 |
498 | )) |
499 | ); |
500 | |
4c105333 |
501 | Class::MOP::Method->meta->add_attribute( |
5e607260 |
502 | Class::MOP::Attribute->new('associated_metaclass' => ( |
5e607260 |
503 | reader => { 'associated_metaclass' => \&Class::MOP::Method::associated_metaclass }, |
504 | )) |
505 | ); |
506 | |
507 | Class::MOP::Method->meta->add_attribute( |
8683db0e |
508 | Class::MOP::Attribute->new('package_name' => ( |
4c105333 |
509 | reader => { 'package_name' => \&Class::MOP::Method::package_name }, |
510 | )) |
511 | ); |
512 | |
513 | Class::MOP::Method->meta->add_attribute( |
8683db0e |
514 | Class::MOP::Attribute->new('name' => ( |
4c105333 |
515 | reader => { 'name' => \&Class::MOP::Method::name }, |
516 | )) |
517 | ); |
518 | |
1a29bc4d |
519 | # FIMXE prime candidate for immutablization |
4c105333 |
520 | Class::MOP::Method->meta->add_method('wrap' => sub { |
5caf45ce |
521 | my ( $class, @args ) = @_; |
522 | |
523 | unshift @args, 'body' if @args % 2 == 1; |
524 | |
525 | my %options = @args; |
526 | my $code = $options{body}; |
4c105333 |
527 | |
9b522fc4 |
528 | ('CODE' eq ref($code)) |
4c105333 |
529 | || confess "You must supply a CODE reference to bless, not (" . ($code || 'undef') . ")"; |
530 | |
b38f3848 |
531 | ($options{package_name} && $options{name}) |
532 | || confess "You must supply the package_name and name parameters"; |
533 | |
4c105333 |
534 | # return the new object |
5caf45ce |
535 | $class->meta->new_object(%options); |
4c105333 |
536 | }); |
537 | |
538 | Class::MOP::Method->meta->add_method('clone' => sub { |
539 | my $self = shift; |
540 | $self->meta->clone_object($self, @_); |
541 | }); |
542 | |
b6164407 |
543 | ## -------------------------------------------------------- |
544 | ## Class::MOP::Method::Wrapped |
545 | |
546 | # NOTE: |
1d68af04 |
547 | # the way this item is initialized, this |
548 | # really does not follow the standard |
549 | # practices of attributes, but we put |
b6164407 |
550 | # it here for completeness |
551 | Class::MOP::Method::Wrapped->meta->add_attribute( |
8683db0e |
552 | Class::MOP::Attribute->new('modifier_table') |
b6164407 |
553 | ); |
554 | |
555 | ## -------------------------------------------------------- |
565f0cbb |
556 | ## Class::MOP::Method::Generated |
557 | |
558 | Class::MOP::Method::Generated->meta->add_attribute( |
8683db0e |
559 | Class::MOP::Attribute->new('is_inline' => ( |
565f0cbb |
560 | reader => { 'is_inline' => \&Class::MOP::Method::Generated::is_inline }, |
4c105333 |
561 | default => 0, |
1d68af04 |
562 | )) |
565f0cbb |
563 | ); |
564 | |
4c105333 |
565 | Class::MOP::Method::Generated->meta->add_method('new' => sub { |
566 | my ($class, %options) = @_; |
b38f3848 |
567 | ($options{package_name} && $options{name}) |
568 | || confess "You must supply the package_name and name parameters"; |
4c105333 |
569 | my $self = $class->meta->new_object(%options); |
570 | $self->initialize_body; |
571 | $self; |
572 | }); |
573 | |
565f0cbb |
574 | ## -------------------------------------------------------- |
d90b42a6 |
575 | ## Class::MOP::Method::Accessor |
576 | |
577 | Class::MOP::Method::Accessor->meta->add_attribute( |
8683db0e |
578 | Class::MOP::Attribute->new('attribute' => ( |
1d68af04 |
579 | reader => { |
580 | 'associated_attribute' => \&Class::MOP::Method::Accessor::associated_attribute |
d90b42a6 |
581 | }, |
1d68af04 |
582 | )) |
d90b42a6 |
583 | ); |
584 | |
585 | Class::MOP::Method::Accessor->meta->add_attribute( |
8683db0e |
586 | Class::MOP::Attribute->new('accessor_type' => ( |
c23184fc |
587 | reader => { 'accessor_type' => \&Class::MOP::Method::Accessor::accessor_type }, |
1d68af04 |
588 | )) |
d90b42a6 |
589 | ); |
590 | |
4c105333 |
591 | Class::MOP::Method::Accessor->meta->add_method('new' => sub { |
592 | my $class = shift; |
593 | my %options = @_; |
594 | |
595 | (exists $options{attribute}) |
596 | || confess "You must supply an attribute to construct with"; |
597 | |
598 | (exists $options{accessor_type}) |
599 | || confess "You must supply an accessor_type to construct with"; |
600 | |
601 | (Scalar::Util::blessed($options{attribute}) && $options{attribute}->isa('Class::MOP::Attribute')) |
602 | || confess "You must supply an attribute which is a 'Class::MOP::Attribute' instance"; |
603 | |
b38f3848 |
604 | ($options{package_name} && $options{name}) |
605 | || confess "You must supply the package_name and name parameters"; |
606 | |
4c105333 |
607 | # return the new object |
608 | my $self = $class->meta->new_object(%options); |
609 | |
610 | # we don't want this creating |
611 | # a cycle in the code, if not |
612 | # needed |
8683db0e |
613 | Scalar::Util::weaken($self->{'attribute'}); |
4c105333 |
614 | |
615 | $self->initialize_body; |
616 | |
617 | $self; |
618 | }); |
619 | |
d90b42a6 |
620 | |
621 | ## -------------------------------------------------------- |
622 | ## Class::MOP::Method::Constructor |
623 | |
624 | Class::MOP::Method::Constructor->meta->add_attribute( |
8683db0e |
625 | Class::MOP::Attribute->new('options' => ( |
1d68af04 |
626 | reader => { |
627 | 'options' => \&Class::MOP::Method::Constructor::options |
d90b42a6 |
628 | }, |
4c105333 |
629 | default => sub { +{} } |
1d68af04 |
630 | )) |
d90b42a6 |
631 | ); |
632 | |
633 | Class::MOP::Method::Constructor->meta->add_attribute( |
8683db0e |
634 | Class::MOP::Attribute->new('associated_metaclass' => ( |
e8a38403 |
635 | init_arg => "metaclass", # FIXME alias and rename |
1d68af04 |
636 | reader => { |
637 | 'associated_metaclass' => \&Class::MOP::Method::Constructor::associated_metaclass |
638 | }, |
639 | )) |
d90b42a6 |
640 | ); |
641 | |
4c105333 |
642 | Class::MOP::Method::Constructor->meta->add_method('new' => sub { |
643 | my $class = shift; |
644 | my %options = @_; |
645 | |
646 | (Scalar::Util::blessed $options{metaclass} && $options{metaclass}->isa('Class::MOP::Class')) |
647 | || confess "You must pass a metaclass instance if you want to inline" |
648 | if $options{is_inline}; |
649 | |
b38f3848 |
650 | ($options{package_name} && $options{name}) |
651 | || confess "You must supply the package_name and name parameters"; |
652 | |
4c105333 |
653 | # return the new object |
654 | my $self = $class->meta->new_object(%options); |
655 | |
656 | # we don't want this creating |
657 | # a cycle in the code, if not |
658 | # needed |
8683db0e |
659 | Scalar::Util::weaken($self->{'associated_metaclass'}); |
4c105333 |
660 | |
661 | $self->initialize_body; |
662 | |
663 | $self; |
664 | }); |
665 | |
d90b42a6 |
666 | ## -------------------------------------------------------- |
86482605 |
667 | ## Class::MOP::Instance |
668 | |
669 | # NOTE: |
1d68af04 |
670 | # these don't yet do much of anything, but are just |
86482605 |
671 | # included for completeness |
672 | |
673 | Class::MOP::Instance->meta->add_attribute( |
74890687 |
674 | Class::MOP::Attribute->new('associated_metaclass', |
675 | reader => { associated_metaclass => \&Class::MOP::Instance::associated_metaclass }, |
676 | ), |
86482605 |
677 | ); |
678 | |
679 | Class::MOP::Instance->meta->add_attribute( |
74890687 |
680 | Class::MOP::Attribute->new('_class_name', |
681 | init_arg => undef, |
682 | reader => { _class_name => \&Class::MOP::Instance::_class_name }, |
683 | #lazy => 1, # not yet supported by Class::MOP but out our version does it anyway |
684 | #default => sub { $_[0]->associated_metaclass->name }, |
685 | ), |
686 | ); |
687 | |
688 | Class::MOP::Instance->meta->add_attribute( |
689 | Class::MOP::Attribute->new('attributes', |
690 | reader => { attributes => \&Class::MOP::Instance::attributes }, |
691 | ), |
32bfc810 |
692 | ); |
693 | |
694 | Class::MOP::Instance->meta->add_attribute( |
74890687 |
695 | Class::MOP::Attribute->new('slots', |
696 | reader => { slots => \&Class::MOP::Instance::slots }, |
697 | ), |
86482605 |
698 | ); |
699 | |
63d08a9e |
700 | Class::MOP::Instance->meta->add_attribute( |
74890687 |
701 | Class::MOP::Attribute->new('slot_hash', |
702 | reader => { slot_hash => \&Class::MOP::Instance::slot_hash }, |
703 | ), |
63d08a9e |
704 | ); |
705 | |
706 | |
caa051fa |
707 | # we need the meta instance of the meta instance to be created now, in order |
708 | # for the constructor to be able to use it |
709 | Class::MOP::Instance->meta->get_meta_instance; |
710 | |
711 | Class::MOP::Instance->meta->add_method('new' => sub { |
712 | my $class = shift; |
713 | my $options = $class->BUILDARGS(@_); |
714 | |
715 | my $self = $class->meta->new_object(%$options); |
716 | |
717 | Scalar::Util::weaken($self->{'associated_metaclass'}); |
718 | |
719 | $self; |
720 | }); |
721 | |
722 | # pretend the add_method never happenned. it hasn't yet affected anything |
723 | undef Class::MOP::Instance->meta->{_package_cache_flag}; |
724 | |
86482605 |
725 | ## -------------------------------------------------------- |
f0480c45 |
726 | ## Now close all the Class::MOP::* classes |
4d47b77f |
727 | |
0b9372a2 |
728 | # NOTE: |
1d68af04 |
729 | # we don't need to inline the |
730 | # constructors or the accessors |
731 | # this only lengthens the compile |
732 | # time of the MOP, and gives us |
0b9372a2 |
733 | # no actual benefits. |
734 | |
735 | $_->meta->make_immutable( |
736 | inline_constructor => 0, |
737 | inline_accessors => 0, |
738 | ) for qw/ |
1d68af04 |
739 | Class::MOP::Package |
740 | Class::MOP::Module |
741 | Class::MOP::Class |
742 | |
0b9372a2 |
743 | Class::MOP::Attribute |
1d68af04 |
744 | Class::MOP::Method |
745 | Class::MOP::Instance |
746 | |
747 | Class::MOP::Object |
0b9372a2 |
748 | |
565f0cbb |
749 | Class::MOP::Method::Generated |
1d68af04 |
750 | |
ba38bf08 |
751 | Class::MOP::Method::Accessor |
1d68af04 |
752 | Class::MOP::Method::Constructor |
753 | Class::MOP::Method::Wrapped |
0b9372a2 |
754 | /; |
b6164407 |
755 | |
94b19069 |
756 | 1; |
757 | |
758 | __END__ |
759 | |
760 | =pod |
761 | |
1d68af04 |
762 | =head1 NAME |
94b19069 |
763 | |
764 | Class::MOP - A Meta Object Protocol for Perl 5 |
765 | |
94b19069 |
766 | =head1 DESCRIPTON |
767 | |
127d39a7 |
768 | This module is a fully functioning meta object protocol for the |
1d68af04 |
769 | Perl 5 object system. It makes no attempt to change the behavior or |
770 | characteristics of the Perl 5 object system, only to create a |
27e31eaf |
771 | protocol for its manipulation and introspection. |
94b19069 |
772 | |
1d68af04 |
773 | That said, it does attempt to create the tools for building a rich |
774 | set of extensions to the Perl 5 object system. Every attempt has been |
775 | made for these tools to keep to the spirit of the Perl 5 object |
94b19069 |
776 | system that we all know and love. |
777 | |
1d68af04 |
778 | This documentation is admittedly sparse on details, as time permits |
779 | I will try to improve them. For now, I suggest looking at the items |
780 | listed in the L<SEE ALSO> section for more information. In particular |
781 | the book "The Art of the Meta Object Protocol" was very influential |
40483095 |
782 | in the development of this system. |
783 | |
bfe4d0fc |
784 | =head2 What is a Meta Object Protocol? |
785 | |
1d68af04 |
786 | A meta object protocol is an API to an object system. |
bfe4d0fc |
787 | |
1d68af04 |
788 | To be more specific, it is a set of abstractions of the components of |
789 | an object system (typically things like; classes, object, methods, |
790 | object attributes, etc.). These abstractions can then be used to both |
bfe4d0fc |
791 | inspect and manipulate the object system which they describe. |
792 | |
1d68af04 |
793 | It can be said that there are two MOPs for any object system; the |
794 | implicit MOP, and the explicit MOP. The implicit MOP handles things |
795 | like method dispatch or inheritance, which happen automatically as |
796 | part of how the object system works. The explicit MOP typically |
797 | handles the introspection/reflection features of the object system. |
798 | All object systems have implicit MOPs, without one, they would not |
799 | work. Explict MOPs however as less common, and depending on the |
800 | language can vary from restrictive (Reflection in Java or C#) to |
801 | wide open (CLOS is a perfect example). |
bfe4d0fc |
802 | |
e16da3e6 |
803 | =head2 Yet Another Class Builder!! Why? |
804 | |
1d68af04 |
805 | This is B<not> a class builder so much as it is a I<class builder |
806 | B<builder>>. My intent is that an end user does not use this module |
807 | directly, but instead this module is used by module authors to |
808 | build extensions and features onto the Perl 5 object system. |
e16da3e6 |
809 | |
94b19069 |
810 | =head2 Who is this module for? |
811 | |
1d68af04 |
812 | This module is specifically for anyone who has ever created or |
813 | wanted to create a module for the Class:: namespace. The tools which |
814 | this module will provide will hopefully make it easier to do more |
815 | complex things with Perl 5 classes by removing such barriers as |
816 | the need to hack the symbol tables, or understand the fine details |
817 | of method dispatch. |
94b19069 |
818 | |
bfe4d0fc |
819 | =head2 What changes do I have to make to use this module? |
820 | |
1d68af04 |
821 | This module was designed to be as unintrusive as possible. Many of |
822 | its features are accessible without B<any> change to your existsing |
823 | code at all. It is meant to be a compliment to your existing code and |
824 | not an intrusion on your code base. Unlike many other B<Class::> |
825 | modules, this module B<does not> require you subclass it, or even that |
826 | you C<use> it in within your module's package. |
bfe4d0fc |
827 | |
1d68af04 |
828 | The only features which requires additions to your code are the |
2eb717d5 |
829 | attribute handling and instance construction features, and these are |
1d68af04 |
830 | both completely optional features. The only reason for this is because |
831 | Perl 5's object system does not actually have these features built |
2eb717d5 |
832 | in. More information about this feature can be found below. |
bfe4d0fc |
833 | |
834 | =head2 A Note about Performance? |
835 | |
1d68af04 |
836 | It is a common misconception that explict MOPs are performance drains. |
837 | But this is not a universal truth at all, it is an side-effect of |
838 | specific implementations. For instance, using Java reflection is much |
839 | slower because the JVM cannot take advantage of any compiler |
840 | optimizations, and the JVM has to deal with much more runtime type |
841 | information as well. Reflection in C# is marginally better as it was |
842 | designed into the language and runtime (the CLR). In contrast, CLOS |
843 | (the Common Lisp Object System) was built to support an explicit MOP, |
844 | and so performance is tuned for it. |
845 | |
846 | This library in particular does it's absolute best to avoid putting |
847 | B<any> drain at all upon your code's performance. In fact, by itself |
848 | it does nothing to affect your existing code. So you only pay for |
2eb717d5 |
849 | what you actually use. |
bfe4d0fc |
850 | |
550d56db |
851 | =head2 About Metaclass compatibility |
852 | |
1d68af04 |
853 | This module makes sure that all metaclasses created are both upwards |
854 | and downwards compatible. The topic of metaclass compatibility is |
855 | highly esoteric and is something only encountered when doing deep and |
856 | involved metaclass hacking. There are two basic kinds of metaclass |
857 | incompatibility; upwards and downwards. |
550d56db |
858 | |
1d68af04 |
859 | Upwards metaclass compatibility means that the metaclass of a |
860 | given class is either the same as (or a subclass of) all of the |
550d56db |
861 | class's ancestors. |
862 | |
1d68af04 |
863 | Downward metaclass compatibility means that the metaclasses of a |
864 | given class's anscestors are all either the same as (or a subclass |
550d56db |
865 | of) that metaclass. |
866 | |
1d68af04 |
867 | Here is a diagram showing a set of two classes (C<A> and C<B>) and |
868 | two metaclasses (C<Meta::A> and C<Meta::B>) which have correct |
550d56db |
869 | metaclass compatibility both upwards and downwards. |
870 | |
871 | +---------+ +---------+ |
872 | | Meta::A |<----| Meta::B | <....... (instance of ) |
1d68af04 |
873 | +---------+ +---------+ <------- (inherits from) |
550d56db |
874 | ^ ^ |
875 | : : |
876 | +---------+ +---------+ |
877 | | A |<----| B | |
878 | +---------+ +---------+ |
879 | |
1d68af04 |
880 | As I said this is a highly esoteric topic and one you will only run |
881 | into if you do a lot of subclassing of B<Class::MOP::Class>. If you |
882 | are interested in why this is an issue see the paper |
883 | I<Uniform and safe metaclass composition> linked to in the |
550d56db |
884 | L<SEE ALSO> section of this document. |
885 | |
aa448b16 |
886 | =head2 Using custom metaclasses |
887 | |
1d68af04 |
888 | Always use the metaclass pragma when using a custom metaclass, this |
889 | will ensure the proper initialization order and not accidentely |
890 | create an incorrect type of metaclass for you. This is a very rare |
891 | problem, and one which can only occur if you are doing deep metaclass |
aa448b16 |
892 | programming. So in other words, don't worry about it. |
893 | |
94b19069 |
894 | =head1 PROTOCOLS |
895 | |
127d39a7 |
896 | The protocol is divided into 4 main sub-protocols: |
94b19069 |
897 | |
898 | =over 4 |
899 | |
900 | =item The Class protocol |
901 | |
1d68af04 |
902 | This provides a means of manipulating and introspecting a Perl 5 |
903 | class. It handles all of symbol table hacking for you, and provides |
94b19069 |
904 | a rich set of methods that go beyond simple package introspection. |
905 | |
552e3d24 |
906 | See L<Class::MOP::Class> for more details. |
907 | |
94b19069 |
908 | =item The Attribute protocol |
909 | |
1d68af04 |
910 | This provides a consistent represenation for an attribute of a |
911 | Perl 5 class. Since there are so many ways to create and handle |
127d39a7 |
912 | attributes in Perl 5 OO, this attempts to provide as much of a |
1d68af04 |
913 | unified approach as possible, while giving the freedom and |
94b19069 |
914 | flexibility to subclass for specialization. |
915 | |
552e3d24 |
916 | See L<Class::MOP::Attribute> for more details. |
917 | |
94b19069 |
918 | =item The Method protocol |
919 | |
1d68af04 |
920 | This provides a means of manipulating and introspecting methods in |
921 | the Perl 5 object system. As with attributes, there are many ways to |
922 | approach this topic, so we try to keep it pretty basic, while still |
94b19069 |
923 | making it possible to extend the system in many ways. |
924 | |
552e3d24 |
925 | See L<Class::MOP::Method> for more details. |
94b19069 |
926 | |
127d39a7 |
927 | =item The Instance protocol |
928 | |
929 | This provides a layer of abstraction for creating object instances. |
930 | Since the other layers use this protocol, it is relatively easy to |
931 | change the type of your instances from the default HASH ref to other |
932 | types of references. Several examples are provided in the F<examples/> |
933 | directory included in this distribution. |
934 | |
935 | See L<Class::MOP::Instance> for more details. |
936 | |
94b19069 |
937 | =back |
938 | |
be7677c7 |
939 | =head1 FUNCTIONS |
940 | |
c1d5345a |
941 | =head2 Constants |
942 | |
943 | =over 4 |
944 | |
945 | =item I<IS_RUNNING_ON_5_10> |
946 | |
947 | We set this constant depending on what version perl we are on, this |
948 | allows us to take advantage of new 5.10 features and stay backwards |
949 | compat. |
950 | |
9efe16ca |
951 | =item I<HAVE_ISAREV> |
952 | |
953 | Whether or not C<mro> provides C<get_isarev>, a much faster way to get all the |
954 | subclasses of a certain class. |
955 | |
c1d5345a |
956 | =back |
957 | |
448b6e55 |
958 | =head2 Utility functions |
959 | |
960 | =over 4 |
961 | |
962 | =item B<load_class ($class_name)> |
963 | |
1d68af04 |
964 | This will load a given C<$class_name> and if it does not have an |
448b6e55 |
965 | already initialized metaclass, then it will intialize one for it. |
127d39a7 |
966 | This function can be used in place of tricks like |
967 | C<eval "use $module"> or using C<require>. |
448b6e55 |
968 | |
969 | =item B<is_class_loaded ($class_name)> |
970 | |
1d68af04 |
971 | This will return a boolean depending on if the C<$class_name> has |
972 | been loaded. |
448b6e55 |
973 | |
1d68af04 |
974 | NOTE: This does a basic check of the symbol table to try and |
448b6e55 |
975 | determine as best it can if the C<$class_name> is loaded, it |
1d68af04 |
976 | is probably correct about 99% of the time. |
448b6e55 |
977 | |
b1f5f41d |
978 | =item B<check_package_cache_flag ($pkg)> |
e0e4674a |
979 | |
127d39a7 |
980 | This will return an integer that is managed by C<Class::MOP::Class> |
981 | to determine if a module's symbol table has been altered. |
982 | |
983 | In Perl 5.10 or greater, this flag is package specific. However in |
984 | versions prior to 5.10, this will use the C<PL_sub_generation> variable |
985 | which is not package specific. |
986 | |
e0e4674a |
987 | =item B<get_code_info ($code)> |
988 | |
127d39a7 |
989 | This function returns two values, the name of the package the C<$code> |
990 | is from and the name of the C<$code> itself. This is used by several |
991 | elements of the MOP to detemine where a given C<$code> reference is from. |
992 | |
4c105333 |
993 | =item B<subname ($name, $code)> |
994 | |
995 | B<NOTE: DO NOT USE THIS FUNCTION, IT IS FOR INTERNAL USE ONLY!> |
996 | |
997 | If possible, we will load the L<Sub::Name> module and this will function |
998 | as C<Sub::Name::subname> does, otherwise it will just return the C<$code> |
999 | argument. |
1000 | |
448b6e55 |
1001 | =back |
1002 | |
1003 | =head2 Metaclass cache functions |
1004 | |
1d68af04 |
1005 | Class::MOP holds a cache of metaclasses, the following are functions |
1006 | (B<not methods>) which can be used to access that cache. It is not |
1007 | recommended that you mess with this, bad things could happen. But if |
be7677c7 |
1008 | you are brave and willing to risk it, go for it. |
1009 | |
1010 | =over 4 |
1011 | |
1012 | =item B<get_all_metaclasses> |
1013 | |
1d68af04 |
1014 | This will return an hash of all the metaclass instances that have |
1015 | been cached by B<Class::MOP::Class> keyed by the package name. |
b9d9fc0b |
1016 | |
be7677c7 |
1017 | =item B<get_all_metaclass_instances> |
1018 | |
1d68af04 |
1019 | This will return an array of all the metaclass instances that have |
b9d9fc0b |
1020 | been cached by B<Class::MOP::Class>. |
1021 | |
be7677c7 |
1022 | =item B<get_all_metaclass_names> |
1023 | |
1d68af04 |
1024 | This will return an array of all the metaclass names that have |
b9d9fc0b |
1025 | been cached by B<Class::MOP::Class>. |
1026 | |
be7677c7 |
1027 | =item B<get_metaclass_by_name ($name)> |
1028 | |
127d39a7 |
1029 | This will return a cached B<Class::MOP::Class> instance of nothing |
1030 | if no metaclass exist by that C<$name>. |
1031 | |
be7677c7 |
1032 | =item B<store_metaclass_by_name ($name, $meta)> |
1033 | |
127d39a7 |
1034 | This will store a metaclass in the cache at the supplied C<$key>. |
1035 | |
be7677c7 |
1036 | =item B<weaken_metaclass ($name)> |
1037 | |
127d39a7 |
1038 | In rare cases it is desireable to store a weakened reference in |
1039 | the metaclass cache. This function will weaken the reference to |
1040 | the metaclass stored in C<$name>. |
1041 | |
be7677c7 |
1042 | =item B<does_metaclass_exist ($name)> |
1043 | |
127d39a7 |
1044 | This will return true of there exists a metaclass stored in the |
1045 | C<$name> key and return false otherwise. |
1046 | |
be7677c7 |
1047 | =item B<remove_metaclass_by_name ($name)> |
1048 | |
127d39a7 |
1049 | This will remove a the metaclass stored in the C<$name> key. |
1050 | |
be7677c7 |
1051 | =back |
1052 | |
552e3d24 |
1053 | =head1 SEE ALSO |
8b978dd5 |
1054 | |
552e3d24 |
1055 | =head2 Books |
8b978dd5 |
1056 | |
1d68af04 |
1057 | There are very few books out on Meta Object Protocols and Metaclasses |
1058 | because it is such an esoteric topic. The following books are really |
1059 | the only ones I have found. If you know of any more, B<I<please>> |
a2e85e6c |
1060 | email me and let me know, I would love to hear about them. |
1061 | |
8b978dd5 |
1062 | =over 4 |
1063 | |
552e3d24 |
1064 | =item "The Art of the Meta Object Protocol" |
8b978dd5 |
1065 | |
552e3d24 |
1066 | =item "Advances in Object-Oriented Metalevel Architecture and Reflection" |
8b978dd5 |
1067 | |
b51af7f9 |
1068 | =item "Putting MetaClasses to Work" |
1069 | |
a2e85e6c |
1070 | =item "Smalltalk: The Language" |
1071 | |
94b19069 |
1072 | =back |
1073 | |
550d56db |
1074 | =head2 Papers |
1075 | |
1076 | =over 4 |
1077 | |
1078 | =item Uniform and safe metaclass composition |
1079 | |
1d68af04 |
1080 | An excellent paper by the people who brought us the original Traits paper. |
1081 | This paper is on how Traits can be used to do safe metaclass composition, |
1082 | and offers an excellent introduction section which delves into the topic of |
550d56db |
1083 | metaclass compatibility. |
1084 | |
1085 | L<http://www.iam.unibe.ch/~scg/Archive/Papers/Duca05ySafeMetaclassTrait.pdf> |
1086 | |
1087 | =item Safe Metaclass Programming |
1088 | |
1d68af04 |
1089 | This paper seems to precede the above paper, and propose a mix-in based |
1090 | approach as opposed to the Traits based approach. Both papers have similar |
1091 | information on the metaclass compatibility problem space. |
550d56db |
1092 | |
1093 | L<http://citeseer.ist.psu.edu/37617.html> |
1094 | |
1095 | =back |
1096 | |
552e3d24 |
1097 | =head2 Prior Art |
8b978dd5 |
1098 | |
1099 | =over 4 |
1100 | |
7184ca14 |
1101 | =item The Perl 6 MetaModel work in the Pugs project |
8b978dd5 |
1102 | |
1103 | =over 4 |
1104 | |
552e3d24 |
1105 | =item L<http://svn.openfoundry.org/pugs/perl5/Perl6-MetaModel> |
8b978dd5 |
1106 | |
552e3d24 |
1107 | =item L<http://svn.openfoundry.org/pugs/perl5/Perl6-ObjectSpace> |
8b978dd5 |
1108 | |
1109 | =back |
1110 | |
94b19069 |
1111 | =back |
1112 | |
1d68af04 |
1113 | =head2 Articles |
f8dfcfb7 |
1114 | |
1115 | =over 4 |
1116 | |
1d68af04 |
1117 | =item CPAN Module Review of Class::MOP |
f8dfcfb7 |
1118 | |
1119 | L<http://www.oreillynet.com/onlamp/blog/2006/06/cpan_module_review_classmop.html> |
1120 | |
1121 | =back |
1122 | |
a2e85e6c |
1123 | =head1 SIMILAR MODULES |
1124 | |
1d68af04 |
1125 | As I have said above, this module is a class-builder-builder, so it is |
1126 | not the same thing as modules like L<Class::Accessor> and |
1127 | L<Class::MethodMaker>. That being said there are very few modules on CPAN |
1128 | with similar goals to this module. The one I have found which is most |
1129 | like this module is L<Class::Meta>, although it's philosophy and the MOP it |
1130 | creates are very different from this modules. |
94b19069 |
1131 | |
a2e85e6c |
1132 | =head1 BUGS |
1133 | |
1d68af04 |
1134 | All complex software has bugs lurking in it, and this module is no |
a2e85e6c |
1135 | exception. If you find a bug please either email me, or add the bug |
1136 | to cpan-RT. |
1137 | |
1138 | =head1 ACKNOWLEDGEMENTS |
1139 | |
1140 | =over 4 |
1141 | |
b9d9fc0b |
1142 | =item Rob Kinyon |
a2e85e6c |
1143 | |
1d68af04 |
1144 | Thanks to Rob for actually getting the development of this module kick-started. |
a2e85e6c |
1145 | |
1146 | =back |
1147 | |
1a09d9cc |
1148 | =head1 AUTHORS |
94b19069 |
1149 | |
a2e85e6c |
1150 | Stevan Little E<lt>stevan@iinteractive.comE<gt> |
552e3d24 |
1151 | |
9c8cda90 |
1152 | B<with contributions from:> |
1153 | |
1154 | Brandon (blblack) Black |
1155 | |
1156 | Guillermo (groditi) Roditi |
1157 | |
9195ddff |
1158 | Matt (mst) Trout |
1159 | |
9c8cda90 |
1160 | Rob (robkinyon) Kinyon |
1161 | |
1162 | Yuval (nothingmuch) Kogman |
1a09d9cc |
1163 | |
f430cfa4 |
1164 | Scott (konobi) McWhirter |
1165 | |
94b19069 |
1166 | =head1 COPYRIGHT AND LICENSE |
1167 | |
69e3ab0a |
1168 | Copyright 2006-2008 by Infinity Interactive, Inc. |
94b19069 |
1169 | |
1170 | L<http://www.iinteractive.com> |
1171 | |
1172 | This library is free software; you can redistribute it and/or modify |
1d68af04 |
1173 | it under the same terms as Perl itself. |
94b19069 |
1174 | |
1175 | =cut |