Commit | Line | Data |
e606ae5f |
1 | package Moose::Exporter; |
2 | |
3 | use strict; |
4 | use warnings; |
5 | |
9039e8ec |
6 | our $VERSION = '0.89_01'; |
ae18d5ec |
7 | $VERSION = eval $VERSION; |
8 | our $AUTHORITY = 'cpan:STEVAN'; |
9 | |
e606ae5f |
10 | use Class::MOP; |
11 | use List::MoreUtils qw( first_index uniq ); |
12 | use Moose::Util::MetaRole; |
091ac4b7 |
13 | use Sub::Exporter 0.980; |
9f2230e9 |
14 | use Sub::Name qw(subname); |
e606ae5f |
15 | |
16 | my %EXPORT_SPEC; |
17 | |
18 | sub setup_import_methods { |
19 | my ( $class, %args ) = @_; |
20 | |
21 | my $exporting_package = $args{exporting_package} ||= caller(); |
22 | |
95056a1e |
23 | $class->build_import_methods( |
24 | %args, |
25 | install => [qw(import unimport init_meta)] |
26 | ); |
e606ae5f |
27 | } |
28 | |
29 | sub build_import_methods { |
30 | my ( $class, %args ) = @_; |
31 | |
32 | my $exporting_package = $args{exporting_package} ||= caller(); |
33 | |
34 | $EXPORT_SPEC{$exporting_package} = \%args; |
35 | |
36 | my @exports_from = $class->_follow_also( $exporting_package ); |
37 | |
38 | my $export_recorder = {}; |
39 | |
0661fc1a |
40 | my ( $exports, $is_removable ) |
e05fb8ae |
41 | = $class->_make_sub_exporter_params( |
f44ec924 |
42 | [ @exports_from, $exporting_package ], $export_recorder ); |
e606ae5f |
43 | |
44 | my $exporter = Sub::Exporter::build_exporter( |
45 | { |
46 | exports => $exports, |
0661fc1a |
47 | groups => { default => [':all'] } |
e606ae5f |
48 | } |
49 | ); |
50 | |
95056a1e |
51 | my %methods; |
e606ae5f |
52 | # $args{_export_to_main} exists for backwards compat, because |
53 | # Moose::Util::TypeConstraints did export to main (unlike Moose & |
54 | # Moose::Role). |
95056a1e |
55 | $methods{import} = $class->_make_import_sub( $exporting_package, |
56 | $exporter, \@exports_from, $args{_export_to_main} ); |
e606ae5f |
57 | |
95056a1e |
58 | $methods{unimport} = $class->_make_unimport_sub( $exporting_package, |
59 | $exports, $is_removable, $export_recorder ); |
60 | |
61 | $methods{init_meta} = $class->_make_init_meta( $exporting_package, |
62 | \%args ); |
63 | |
64 | my $package = Class::MOP::Package->initialize($exporting_package); |
906eabcd |
65 | for my $to_install ( @{ $args{install} || [] } ) { |
95056a1e |
66 | my $symbol = '&' . $to_install; |
906eabcd |
67 | next |
68 | unless $methods{$to_install} |
69 | && !$package->has_package_symbol($symbol); |
70 | $package->add_package_symbol( $symbol, $methods{$to_install} ); |
95056a1e |
71 | } |
e606ae5f |
72 | |
95056a1e |
73 | return ( $methods{import}, $methods{unimport}, $methods{init_meta} ) |
e606ae5f |
74 | } |
75 | |
76 | { |
77 | my $seen = {}; |
78 | |
79 | sub _follow_also { |
80 | my $class = shift; |
81 | my $exporting_package = shift; |
82 | |
83 | local %$seen = ( $exporting_package => 1 ); |
84 | |
85 | return uniq( _follow_also_real($exporting_package) ); |
86 | } |
87 | |
88 | sub _follow_also_real { |
89 | my $exporting_package = shift; |
90 | |
ba1a3c2f |
91 | if (!exists $EXPORT_SPEC{$exporting_package}) { |
92 | my $loaded = Class::MOP::is_class_loaded($exporting_package); |
93 | |
94 | die "Package in also ($exporting_package) does not seem to " |
95 | . "use Moose::Exporter" |
96 | . ($loaded ? "" : " (is it loaded?)"); |
97 | } |
e606ae5f |
98 | |
99 | my $also = $EXPORT_SPEC{$exporting_package}{also}; |
100 | |
101 | return unless defined $also; |
102 | |
103 | my @also = ref $also ? @{$also} : $also; |
104 | |
105 | for my $package (@also) |
106 | { |
f5d03831 |
107 | die "Circular reference in also parameter to Moose::Exporter between $exporting_package and $package" |
e606ae5f |
108 | if $seen->{$package}; |
109 | |
110 | $seen->{$package} = 1; |
111 | } |
112 | |
113 | return @also, map { _follow_also_real($_) } @also; |
114 | } |
115 | } |
116 | |
117 | sub _make_sub_exporter_params { |
118 | my $class = shift; |
119 | my $packages = shift; |
120 | my $export_recorder = shift; |
121 | |
122 | my %exports; |
e05fb8ae |
123 | my %is_removable; |
e606ae5f |
124 | |
125 | for my $package ( @{$packages} ) { |
126 | my $args = $EXPORT_SPEC{$package} |
127 | or die "The $package package does not use Moose::Exporter\n"; |
128 | |
5ac14e89 |
129 | for my $name ( @{ $args->{with_meta} } ) { |
0dd4228e |
130 | my $sub = $class->_sub_from_package( $package, $name ) |
131 | or next; |
e6a5040f |
132 | |
e606ae5f |
133 | my $fq_name = $package . '::' . $name; |
134 | |
5ac14e89 |
135 | $exports{$name} = $class->_make_wrapped_sub_with_meta( |
e606ae5f |
136 | $fq_name, |
137 | $sub, |
138 | $export_recorder, |
139 | ); |
e05fb8ae |
140 | |
141 | $is_removable{$name} = 1; |
e606ae5f |
142 | } |
143 | |
5ac14e89 |
144 | for my $name ( @{ $args->{with_caller} } ) { |
0dd4228e |
145 | my $sub = $class->_sub_from_package( $package, $name ) |
146 | or next; |
e6a5040f |
147 | |
45975bce |
148 | my $fq_name = $package . '::' . $name; |
149 | |
5ac14e89 |
150 | $exports{$name} = $class->_make_wrapped_sub( |
45975bce |
151 | $fq_name, |
152 | $sub, |
153 | $export_recorder, |
154 | ); |
155 | |
156 | $is_removable{$name} = 1; |
157 | } |
158 | |
e606ae5f |
159 | for my $name ( @{ $args->{as_is} } ) { |
e6a5040f |
160 | my ($sub, $coderef_name); |
e606ae5f |
161 | |
162 | if ( ref $name ) { |
163 | $sub = $name; |
e05fb8ae |
164 | |
165 | # Even though Moose re-exports things from Carp & |
166 | # Scalar::Util, we don't want to remove those at |
167 | # unimport time, because the importing package may |
168 | # have imported them explicitly ala |
169 | # |
170 | # use Carp qw( confess ); |
171 | # |
172 | # This is a hack. Since we can't know whether they |
173 | # really want to keep these subs or not, we err on the |
174 | # safe side and leave them in. |
175 | my $coderef_pkg; |
e6a5040f |
176 | ( $coderef_pkg, $coderef_name ) |
177 | = Class::MOP::get_code_info($name); |
e05fb8ae |
178 | |
e6a5040f |
179 | $is_removable{$coderef_name} = $coderef_pkg eq $package ? 1 : 0; |
e606ae5f |
180 | } |
181 | else { |
0dd4228e |
182 | $sub = $class->_sub_from_package( $package, $name ) |
183 | or next; |
e6a5040f |
184 | |
e05fb8ae |
185 | $is_removable{$name} = 1; |
e6a5040f |
186 | $coderef_name = $name; |
e606ae5f |
187 | } |
188 | |
189 | $export_recorder->{$sub} = 1; |
190 | |
e6a5040f |
191 | $exports{$coderef_name} = sub {$sub}; |
e606ae5f |
192 | } |
193 | } |
194 | |
0661fc1a |
195 | return ( \%exports, \%is_removable ); |
e606ae5f |
196 | } |
197 | |
0dd4228e |
198 | sub _sub_from_package { |
199 | my $sclass = shift; |
200 | my $package = shift; |
201 | my $name = shift; |
202 | |
203 | my $sub = do { |
204 | no strict 'refs'; |
205 | \&{ $package . '::' . $name }; |
206 | }; |
207 | |
208 | return $sub if defined &$sub; |
209 | |
210 | Carp::cluck |
211 | "Trying to export undefined sub ${package}::${name}"; |
212 | |
213 | return; |
214 | } |
215 | |
96bb13ea |
216 | our $CALLER; |
217 | |
218 | sub _make_wrapped_sub { |
b4f00a34 |
219 | my $self = shift; |
96bb13ea |
220 | my $fq_name = shift; |
221 | my $sub = shift; |
222 | my $export_recorder = shift; |
223 | |
224 | # We need to set the package at import time, so that when |
225 | # package Foo imports has(), we capture "Foo" as the |
226 | # package. This lets other packages call Foo::has() and get |
227 | # the right package. This is done for backwards compatibility |
228 | # with existing production code, not because this is a good |
229 | # idea ;) |
230 | return sub { |
231 | my $caller = $CALLER; |
232 | |
6de00734 |
233 | my $wrapper = $self->_curry_wrapper($sub, $fq_name, $caller); |
b4f00a34 |
234 | |
9f2230e9 |
235 | my $sub = subname($fq_name => $wrapper); |
96bb13ea |
236 | |
237 | $export_recorder->{$sub} = 1; |
238 | |
239 | return $sub; |
240 | }; |
241 | } |
e606ae5f |
242 | |
45975bce |
243 | sub _make_wrapped_sub_with_meta { |
244 | my $self = shift; |
245 | my $fq_name = shift; |
246 | my $sub = shift; |
247 | my $export_recorder = shift; |
248 | |
249 | return sub { |
250 | my $caller = $CALLER; |
251 | |
252 | my $wrapper = $self->_late_curry_wrapper($sub, $fq_name, |
253 | sub { Class::MOP::class_of(shift) } => $caller); |
254 | |
255 | my $sub = subname($fq_name => $wrapper); |
256 | |
257 | $export_recorder->{$sub} = 1; |
258 | |
259 | return $sub; |
260 | }; |
261 | } |
262 | |
263 | sub _make_wrapped_group { |
264 | my $class = shift; |
265 | my $package = shift; # package calling use Moose::Exporter |
266 | my $sub = shift; |
267 | my $export_recorder = shift; |
268 | my $keywords = shift; |
269 | my $is_removable = shift; |
270 | |
271 | return sub { |
272 | my $caller = $CALLER; # package calling use PackageUsingMooseExporter -group => {args} |
273 | |
274 | # there are plenty of ways to deal with telling the code which |
275 | # package it lives in. the last arg (collector hashref) is |
276 | # otherwise unused, so we'll stick the original package in |
277 | # there and act like 'with_caller' by putting the calling |
278 | # package name as the first arg |
279 | $_[0] = $caller; |
280 | $_[3]{from} = $package; |
281 | |
282 | my $named_code = $sub->(@_); |
283 | $named_code ||= { }; |
284 | |
285 | # send invalid return value error up to Sub::Exporter |
286 | unless (ref $named_code eq 'HASH') { |
287 | return $named_code; |
288 | } |
289 | |
290 | for my $name (keys %$named_code) { |
291 | my $code = $named_code->{$name}; |
292 | |
293 | my $fq_name = $package . '::' . $name; |
294 | my $wrapper = $class->_curry_wrapper( |
295 | $code, |
296 | $fq_name, |
297 | $caller |
298 | ); |
299 | |
300 | my $sub = subname( $fq_name => $wrapper ); |
301 | $named_code->{$name} = $sub; |
302 | |
303 | # mark each coderef as ours |
304 | $keywords->{$name} = 1; |
305 | $is_removable->{$name} = 1; |
306 | $export_recorder->{$sub} = 1; |
307 | } |
308 | |
309 | return $named_code; |
310 | }; |
311 | } |
312 | |
6de00734 |
313 | sub _curry_wrapper { |
badbc528 |
314 | my $class = shift; |
b4f00a34 |
315 | my $sub = shift; |
316 | my $fq_name = shift; |
6de00734 |
317 | my @extra = @_; |
b4f00a34 |
318 | |
6de00734 |
319 | my $wrapper = sub { $sub->(@extra, @_) }; |
badbc528 |
320 | if (my $proto = prototype $sub) { |
2d7e979b |
321 | # XXX - Perl's prototype sucks. Use & to make set_prototype |
6de00734 |
322 | # ignore the fact that we're passing "private variables" |
2d7e979b |
323 | &Scalar::Util::set_prototype($wrapper, $proto); |
badbc528 |
324 | } |
325 | return $wrapper; |
b4f00a34 |
326 | } |
327 | |
45975bce |
328 | sub _late_curry_wrapper { |
329 | my $class = shift; |
330 | my $sub = shift; |
331 | my $fq_name = shift; |
332 | my $extra = shift; |
333 | my @ex_args = @_; |
334 | |
335 | my $wrapper = sub { |
336 | # resolve curried arguments at runtime via this closure |
337 | my @curry = ( $extra->( @ex_args ) ); |
338 | return $sub->(@curry, @_); |
339 | }; |
340 | |
341 | if (my $proto = prototype $sub) { |
342 | # XXX - Perl's prototype sucks. Use & to make set_prototype |
343 | # ignore the fact that we're passing "private variables" |
344 | &Scalar::Util::set_prototype($wrapper, $proto); |
345 | } |
346 | return $wrapper; |
347 | } |
348 | |
96bb13ea |
349 | sub _make_import_sub { |
350 | shift; |
351 | my $exporting_package = shift; |
352 | my $exporter = shift; |
353 | my $exports_from = shift; |
354 | my $export_to_main = shift; |
355 | |
356 | return sub { |
357 | |
358 | # I think we could use Sub::Exporter's collector feature |
359 | # to do this, but that would be rather gross, since that |
360 | # feature isn't really designed to return a value to the |
361 | # caller of the exporter sub. |
362 | # |
363 | # Also, this makes sure we preserve backwards compat for |
364 | # _get_caller, so it always sees the arguments in the |
365 | # expected order. |
366 | my $traits; |
367 | ( $traits, @_ ) = _strip_traits(@_); |
368 | |
8f30b86e |
369 | my $metaclass; |
370 | ( $metaclass, @_ ) = _strip_metaclass(@_); |
8a8856de |
371 | $metaclass = Moose::Util::resolve_metaclass_alias( |
372 | 'Class' => $metaclass |
373 | ) if defined $metaclass && length $metaclass; |
8f30b86e |
374 | |
96bb13ea |
375 | # Normally we could look at $_[0], but in some weird cases |
376 | # (involving goto &Moose::import), $_[0] ends as something |
377 | # else (like Squirrel). |
378 | my $class = $exporting_package; |
379 | |
380 | $CALLER = _get_caller(@_); |
381 | |
382 | # this works because both pragmas set $^H (see perldoc |
383 | # perlvar) which affects the current compilation - |
384 | # i.e. the file who use'd us - which is why we don't need |
385 | # to do anything special to make it affect that file |
386 | # rather than this one (which is already compiled) |
387 | |
388 | strict->import; |
389 | warnings->import; |
390 | |
391 | # we should never export to main |
392 | if ( $CALLER eq 'main' && !$export_to_main ) { |
393 | warn |
394 | qq{$class does not export its sugar to the 'main' package.\n}; |
395 | return; |
396 | } |
e606ae5f |
397 | |
96bb13ea |
398 | my $did_init_meta; |
399 | for my $c ( grep { $_->can('init_meta') } $class, @{$exports_from} ) { |
816208bc |
400 | # init_meta can apply a role, which when loaded uses |
401 | # Moose::Exporter, which in turn sets $CALLER, so we need |
402 | # to protect against that. |
fdeb8354 |
403 | local $CALLER = $CALLER; |
89bcd625 |
404 | $c->init_meta( for_class => $CALLER, metaclass => $metaclass ); |
96bb13ea |
405 | $did_init_meta = 1; |
406 | } |
e606ae5f |
407 | |
96bb13ea |
408 | if ( $did_init_meta && @{$traits} ) { |
409 | # The traits will use Moose::Role, which in turn uses |
410 | # Moose::Exporter, which in turn sets $CALLER, so we need |
411 | # to protect against that. |
412 | local $CALLER = $CALLER; |
413 | _apply_meta_traits( $CALLER, $traits ); |
414 | } |
415 | elsif ( @{$traits} ) { |
70ea9161 |
416 | require Moose; |
96bb13ea |
417 | Moose->throw_error( |
418 | "Cannot provide traits when $class does not have an init_meta() method" |
419 | ); |
420 | } |
e606ae5f |
421 | |
96bb13ea |
422 | goto $exporter; |
423 | }; |
e606ae5f |
424 | } |
425 | |
96bb13ea |
426 | |
e606ae5f |
427 | sub _strip_traits { |
428 | my $idx = first_index { $_ eq '-traits' } @_; |
429 | |
430 | return ( [], @_ ) unless $idx >= 0 && $#_ >= $idx + 1; |
431 | |
432 | my $traits = $_[ $idx + 1 ]; |
433 | |
434 | splice @_, $idx, 2; |
435 | |
436 | $traits = [ $traits ] unless ref $traits; |
437 | |
438 | return ( $traits, @_ ); |
439 | } |
440 | |
8f30b86e |
441 | sub _strip_metaclass { |
442 | my $idx = first_index { $_ eq '-metaclass' } @_; |
443 | |
444 | return ( undef, @_ ) unless $idx >= 0 && $#_ >= $idx + 1; |
445 | |
446 | my $metaclass = $_[ $idx + 1 ]; |
447 | |
448 | splice @_, $idx, 2; |
449 | |
450 | return ( $metaclass, @_ ); |
451 | } |
452 | |
e606ae5f |
453 | sub _apply_meta_traits { |
454 | my ( $class, $traits ) = @_; |
455 | |
456 | return unless @{$traits}; |
457 | |
2571a16d |
458 | my $meta = Class::MOP::class_of($class); |
e606ae5f |
459 | |
460 | my $type = ( split /::/, ref $meta )[-1] |
c245d69b |
461 | or Moose->throw_error( |
e606ae5f |
462 | 'Cannot determine metaclass type for trait application . Meta isa ' |
4c0b3599 |
463 | . ref $meta ); |
e606ae5f |
464 | |
465 | my @resolved_traits |
386c056b |
466 | = map { |
467 | ref $_ ? $_ : Moose::Util::resolve_metatrait_alias( $type => $_ ) |
468 | } |
e606ae5f |
469 | @$traits; |
470 | |
471 | return unless @resolved_traits; |
472 | |
473 | Moose::Util::MetaRole::apply_metaclass_roles( |
474 | for_class => $class, |
475 | metaclass_roles => \@resolved_traits, |
476 | ); |
477 | } |
478 | |
479 | sub _get_caller { |
480 | # 1 extra level because it's called by import so there's a layer |
481 | # of indirection |
482 | my $offset = 1; |
483 | |
484 | return |
485 | ( ref $_[1] && defined $_[1]->{into} ) ? $_[1]->{into} |
486 | : ( ref $_[1] && defined $_[1]->{into_level} ) |
487 | ? caller( $offset + $_[1]->{into_level} ) |
488 | : caller($offset); |
489 | } |
490 | |
491 | sub _make_unimport_sub { |
492 | shift; |
493 | my $exporting_package = shift; |
494 | my $exports = shift; |
e05fb8ae |
495 | my $is_removable = shift; |
e606ae5f |
496 | my $export_recorder = shift; |
497 | |
498 | return sub { |
499 | my $caller = scalar caller(); |
500 | Moose::Exporter->_remove_keywords( |
501 | $caller, |
502 | [ keys %{$exports} ], |
e05fb8ae |
503 | $is_removable, |
e606ae5f |
504 | $export_recorder, |
505 | ); |
506 | }; |
507 | } |
508 | |
509 | sub _remove_keywords { |
510 | shift; |
511 | my $package = shift; |
512 | my $keywords = shift; |
e05fb8ae |
513 | my $is_removable = shift; |
e606ae5f |
514 | my $recorded_exports = shift; |
515 | |
516 | no strict 'refs'; |
517 | |
518 | foreach my $name ( @{ $keywords } ) { |
e05fb8ae |
519 | next unless $is_removable->{$name}; |
e606ae5f |
520 | |
521 | if ( defined &{ $package . '::' . $name } ) { |
522 | my $sub = \&{ $package . '::' . $name }; |
523 | |
524 | # make sure it is from us |
525 | next unless $recorded_exports->{$sub}; |
526 | |
527 | # and if it is from us, then undef the slot |
528 | delete ${ $package . '::' }{$name}; |
529 | } |
530 | } |
531 | } |
532 | |
95056a1e |
533 | sub _make_init_meta { |
534 | shift; |
906eabcd |
535 | my $class = shift; |
536 | my $args = shift; |
95056a1e |
537 | |
538 | my %metaclass_roles; |
906eabcd |
539 | for my $role ( |
540 | map {"${_}_roles"} |
541 | qw(metaclass |
542 | attribute_metaclass |
543 | method_metaclass |
544 | wrapped_method_metaclass |
545 | instance_metaclass |
546 | constructor_class |
547 | destructor_class |
548 | error_class |
549 | application_to_class_class |
550 | application_to_role_class |
551 | application_to_instance_class) |
552 | ) { |
95056a1e |
553 | $metaclass_roles{$role} = $args->{$role} if exists $args->{$role}; |
554 | } |
555 | |
556 | my %base_class_roles; |
906eabcd |
557 | %base_class_roles = ( roles => $args->{base_class_roles} ) |
95056a1e |
558 | if exists $args->{base_class_roles}; |
559 | |
560 | return unless %metaclass_roles || %base_class_roles; |
561 | |
562 | return sub { |
563 | shift; |
564 | my %options = @_; |
906eabcd |
565 | |
566 | return unless Class::MOP::class_of( $options{for_class} ); |
567 | |
95056a1e |
568 | Moose::Util::MetaRole::apply_metaclass_roles( |
569 | for_class => $options{for_class}, |
570 | %metaclass_roles, |
571 | ); |
906eabcd |
572 | |
95056a1e |
573 | Moose::Util::MetaRole::apply_base_class_roles( |
574 | for_class => $options{for_class}, |
575 | %base_class_roles, |
906eabcd |
576 | ) |
577 | if Class::MOP::class_of( $options{for_class} ) |
578 | ->isa('Moose::Meta::Class'); |
579 | |
580 | return Class::MOP::class_of( $options{for_class} ); |
95056a1e |
581 | }; |
582 | } |
583 | |
e2fa092d |
584 | sub import { |
585 | strict->import; |
586 | warnings->import; |
587 | } |
588 | |
e606ae5f |
589 | 1; |
590 | |
591 | __END__ |
592 | |
593 | =head1 NAME |
594 | |
595 | Moose::Exporter - make an import() and unimport() just like Moose.pm |
596 | |
597 | =head1 SYNOPSIS |
598 | |
599 | package MyApp::Moose; |
600 | |
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601 | use Moose (); |
602 | use Moose::Exporter; |
603 | |
604 | Moose::Exporter->setup_import_methods( |
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605 | with_meta => [ 'has_rw', 'sugar2' ], |
606 | as_is => [ 'sugar3', \&Some::Random::thing ], |
607 | also => 'Moose', |
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608 | ); |
609 | |
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610 | sub has_rw { |
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611 | my ( $meta, $name, %options ) = @_; |
612 | $meta->add_attribute( |
613 | $name, |
82ad7804 |
614 | is => 'rw', |
615 | %options, |
616 | ); |
617 | } |
618 | |
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619 | # then later ... |
620 | package MyApp::User; |
621 | |
622 | use MyApp::Moose; |
623 | |
624 | has 'name'; |
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625 | has_rw 'size'; |
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626 | thing; |
627 | |
628 | no MyApp::Moose; |
629 | |
630 | =head1 DESCRIPTION |
631 | |
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632 | This module encapsulates the exporting of sugar functions in a |
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633 | C<Moose.pm>-like manner. It does this by building custom C<import>, |
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634 | C<unimport>, and C<init_meta> methods for your module, based on a spec you |
635 | provide. |
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636 | |
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637 | It also lets you "stack" Moose-alike modules so you can export Moose's sugar |
638 | as well as your own, along with sugar from any random C<MooseX> module, as |
639 | long as they all use C<Moose::Exporter>. This feature exists to let you bundle |
640 | a set of MooseX modules into a policy module that developers can use directly |
641 | instead of using Moose itself. |
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642 | |
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643 | To simplify writing exporter modules, C<Moose::Exporter> also imports |
644 | C<strict> and C<warnings> into your exporter module, as well as into |
645 | modules that use it. |
646 | |
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647 | =head1 METHODS |
648 | |
649 | This module provides two public methods: |
650 | |
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651 | =over 4 |
652 | |
653 | =item B<< Moose::Exporter->setup_import_methods(...) >> |
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654 | |
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655 | When you call this method, C<Moose::Exporter> builds custom C<import>, |
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656 | C<unimport>, and C<init_meta> methods for your module. The C<import> method |
657 | will export the functions you specify, and can also re-export functions |
658 | exported by some other module (like C<Moose.pm>). |
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659 | |
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660 | The C<unimport> method cleans the caller's namespace of all the exported |
661 | functions. |
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662 | |
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663 | If you pass any parameters for L<Moose::Util::MetaRole>, this method will |
664 | generate an C<init_meta> for you as well (see below for details). This |
665 | C<init_meta> will call C<Moose::Util::MetaRole::apply_metaclass_roles> and |
666 | C<Moose::Util::MetaRole::apply_base_class_roles> as needed. |
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667 | |
668 | Note that if any of these methods already exist, they will not be |
669 | overridden, you will have to use C<build_import_methods> to get the |
670 | coderef that would be installed. |
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671 | |
672 | This method accepts the following parameters: |
673 | |
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674 | =over 8 |
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675 | |
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676 | =item * with_meta => [ ... ] |
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677 | |
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678 | This list of function I<names only> will be wrapped and then exported. The |
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679 | wrapper will pass the metaclass object for the caller as its first argument. |
680 | |
681 | Many sugar functions will need to use this metaclass object to do something to |
682 | the calling package. |
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683 | |
684 | =item * as_is => [ ... ] |
685 | |
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686 | This list of function names or sub references will be exported as-is. You can |
687 | identify a subroutine by reference, which is handy to re-export some other |
688 | module's functions directly by reference (C<\&Some::Package::function>). |
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689 | |
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690 | If you do export some other package's function, this function will never be |
691 | removed by the C<unimport> method. The reason for this is we cannot know if |
692 | the caller I<also> explicitly imported the sub themselves, and therefore wants |
693 | to keep it. |
e05fb8ae |
694 | |
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695 | =item * also => $name or \@names |
696 | |
697 | This is a list of modules which contain functions that the caller |
698 | wants to export. These modules must also use C<Moose::Exporter>. The |
699 | most common use case will be to export the functions from C<Moose.pm>. |
5ac14e89 |
700 | Functions specified by C<with_meta> or C<as_is> take precedence over |
ae8817b6 |
701 | functions exported by modules specified by C<also>, so that a module |
702 | can selectively override functions exported by another module. |
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703 | |
704 | C<Moose::Exporter> also makes sure all these functions get removed |
705 | when C<unimport> is called. |
706 | |
707 | =back |
708 | |
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709 | Any of the C<*_roles> options for |
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710 | C<Moose::Util::MetaRole::apply_metaclass_roles> and |
711 | C<Moose::Util::MetaRole::base_class_roles> are also acceptable. |
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712 | |
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713 | =item B<< Moose::Exporter->build_import_methods(...) >> |
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714 | |
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715 | Returns two or three code refs, one for C<import>, one for |
716 | C<unimport>, and optionally one for C<init_meta>, if the appropriate |
717 | options are passed in. |
718 | |
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719 | Accepts the additional C<install> option, which accepts an arrayref of method |
720 | names to install into your exporting package. The valid options are C<import>, |
721 | C<unimport>, and C<init_meta>. Calling C<setup_import_methods> is equivalent |
722 | to calling C<build_import_methods> with C<< install => [qw(import unimport |
723 | init_meta)] >> except that it doesn't also return the methods. |
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724 | |
725 | Used by C<setup_import_methods>. |
726 | |
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727 | =back |
728 | |
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729 | =head1 IMPORTING AND init_meta |
730 | |
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731 | If you want to set an alternative base object class or metaclass class, see |
732 | above for details on how this module can call L<Moose::Util::MetaRole> for |
733 | you. |
734 | |
735 | If you want to do something that is not supported by this module, simply |
736 | define an C<init_meta> method in your class. The C<import> method that |
737 | C<Moose::Exporter> generates for you will call this method (if it exists). It |
738 | will always pass the caller to this method via the C<for_class> parameter. |
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739 | |
740 | Most of the time, your C<init_meta> method will probably just call C<< |
741 | Moose->init_meta >> to do the real work: |
742 | |
743 | sub init_meta { |
744 | shift; # our class name |
745 | return Moose->init_meta( @_, metaclass => 'My::Metaclass' ); |
746 | } |
747 | |
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748 | Keep in mind that C<build_import_methods> will return an C<init_meta> |
749 | method for you, which you can also call from within your custom |
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750 | C<init_meta>: |
751 | |
752 | my ( $import, $unimport, $init_meta ) = |
753 | Moose::Exporter->build_import_methods( ... ); |
754 | |
755 | sub import { |
756 | my $class = shift; |
757 | |
758 | ... |
759 | |
760 | $class->$import(...); |
761 | |
762 | ... |
763 | } |
764 | |
765 | sub unimport { goto &$unimport } |
766 | |
767 | sub init_meta { |
768 | my $class = shift; |
769 | |
770 | ... |
771 | |
772 | $class->$init_meta(...); |
773 | |
774 | ... |
775 | } |
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776 | |
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777 | =head1 METACLASS TRAITS |
778 | |
779 | The C<import> method generated by C<Moose::Exporter> will allow the |
780 | user of your module to specify metaclass traits in a C<-traits> |
781 | parameter passed as part of the import: |
782 | |
783 | use Moose -traits => 'My::Meta::Trait'; |
784 | |
785 | use Moose -traits => [ 'My::Meta::Trait', 'My::Other::Trait' ]; |
786 | |
787 | These traits will be applied to the caller's metaclass |
788 | instance. Providing traits for an exporting class that does not create |
789 | a metaclass for the caller is an error. |
790 | |
791 | =head1 AUTHOR |
792 | |
793 | Dave Rolsky E<lt>autarch@urth.orgE<gt> |
794 | |
795 | This is largely a reworking of code in Moose.pm originally written by |
796 | Stevan Little and others. |
797 | |
798 | =head1 COPYRIGHT AND LICENSE |
799 | |
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800 | Copyright 2009 by Infinity Interactive, Inc. |
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801 | |
802 | L<http://www.iinteractive.com> |
803 | |
804 | This library is free software; you can redistribute it and/or modify |
805 | it under the same terms as Perl itself. |
806 | |
807 | =cut |