10 use Scalar::Util 'blessed';
13 use Mouse::Meta::Attribute;
14 use Mouse::Meta::Class;
16 use Mouse::Util::TypeConstraints;
18 our @EXPORT = qw(extends has before after around override super blessed confess with);
20 sub extends { Mouse::Meta::Class->initialize(caller)->superclasses(@_) }
23 my $meta = Mouse::Meta::Class->initialize(caller);
24 $meta->add_attribute(@_);
28 my $meta = Mouse::Meta::Class->initialize(caller);
33 $meta->add_before_method_modifier($_ => $code);
38 my $meta = Mouse::Meta::Class->initialize(caller);
43 $meta->add_after_method_modifier($_ => $code);
48 my $meta = Mouse::Meta::Class->initialize(caller);
53 $meta->add_around_method_modifier($_ => $code);
58 Mouse::Util::apply_all_roles((caller)[0], @_);
66 # This check avoids a recursion loop - see
67 # t/100_bugs/020_super_recursion.t
68 return if defined $SUPER_PACKAGE && $SUPER_PACKAGE ne caller();
69 return unless $SUPER_BODY; $SUPER_BODY->(@SUPER_ARGS);
73 my $meta = Mouse::Meta::Class->initialize(caller);
74 my $pkg = $meta->name;
79 my $body = $pkg->can($name)
80 or confess "You cannot override '$name' because it has no super method";
82 $meta->add_method($name => sub {
83 local $SUPER_PACKAGE = $pkg;
84 local @SUPER_ARGS = @_;
85 local $SUPER_BODY = $body;
92 # This used to be called as a function. This hack preserves
93 # backwards compatibility.
94 if ( $_[0] ne __PACKAGE__ ) {
95 return __PACKAGE__->init_meta(
105 my $class = $args{for_class}
107 "Cannot call init_meta without specifying a for_class");
108 my $base_class = $args{base_class} || 'Mouse::Object';
109 my $metaclass = $args{metaclass} || 'Mouse::Meta::Class';
111 Carp::croak("The Metaclass $metaclass must be a subclass of Mouse::Meta::Class.")
112 unless $metaclass->isa('Mouse::Meta::Class');
114 # make a subtype for each Mouse class
116 unless find_type_constraint($class);
118 my $meta = $metaclass->initialize($class);
119 $meta->superclasses($base_class)
120 unless $meta->superclasses;
124 no warnings 'redefine';
125 *{$class.'::meta'} = sub { $meta };
138 if (ref($_[0]) && ref($_[0]) eq 'HASH') {
144 my $level = delete $opts->{into_level};
145 $level = 0 unless defined $level;
146 my $caller = caller($level);
148 # we should never export to main
149 if ($caller eq 'main') {
150 warn qq{$class does not export its sugar to the 'main' package.\n};
155 for_class => $caller,
159 __PACKAGE__->export_to_level( $level+1, $class, @_);
161 # shortcut for the common case of no type character
163 for my $keyword (@EXPORT) {
164 *{ $caller . '::' . $keyword } = *{__PACKAGE__ . '::' . $keyword};
173 for my $keyword (@EXPORT) {
174 delete ${ $caller . '::' }{$keyword};
181 if (ref($class) || !defined($class) || !length($class)) {
182 my $display = defined($class) ? $class : 'undef';
183 confess "Invalid class name ($display)";
186 return 1 if $class eq 'Mouse::Object';
187 return 1 if is_class_loaded($class);
189 (my $file = "$class.pm") =~ s{::}{/}g;
191 eval { CORE::require($file) };
192 confess "Could not load class ($class) because : $@" if $@;
197 sub is_class_loaded {
200 return 0 if ref($class) || !defined($class) || !length($class);
202 # walk the symbol table tree to avoid autovififying
203 # \*{${main::}{"Foo::"}} == \*main::Foo::
206 foreach my $part (split('::', $class)) {
207 return 0 unless exists ${$$pack}{"${part}::"};
208 $pack = \*{${$$pack}{"${part}::"}};
211 # check for $VERSION or @ISA
212 return 1 if exists ${$$pack}{VERSION}
213 && defined *{${$$pack}{VERSION}}{SCALAR};
214 return 1 if exists ${$$pack}{ISA}
215 && defined *{${$$pack}{ISA}}{ARRAY};
217 # check for any method
218 foreach ( keys %{$$pack} ) {
219 next if substr($_, -2, 2) eq '::';
220 return 1 if defined *{${$$pack}{$_}}{CODE};
228 return unless defined $_[0];
229 my $class = blessed($_[0]) || $_[0];
230 return Mouse::Meta::Class::get_metaclass_by_name($class);
239 Mouse - Moose minus the antlers
244 use Mouse; # automatically turns on strict and warnings
246 has 'x' => (is => 'rw', isa => 'Int');
247 has 'y' => (is => 'rw', isa => 'Int');
260 has 'z' => (is => 'rw', isa => 'Int');
262 after 'clear' => sub {
269 L<Moose> is wonderful. B<Use Moose instead of Mouse.>
271 Unfortunately, Moose has a compile-time penalty. Though significant progress has
272 been made over the years, the compile time penalty is a non-starter for some
275 Mouse aims to alleviate this by providing a subset of Moose's functionality,
278 We're also going as light on dependencies as possible.
279 L<Class::Method::Modifiers> or L<Data::Util> is required if you want support
280 for L</before>, L</after>, and L</around>.
284 Compatibility with Moose has been the utmost concern. Fewer than 1% of the
285 tests fail when run against Moose instead of Mouse. Mouse code coverage is also
286 over 96%. Even the error messages are taken from Moose. The Mouse code just
287 runs the test suite 4x faster.
289 The idea is that, if you need the extra power, you should be able to run
290 C<s/Mouse/Moose/g> on your codebase and have nothing break. To that end,
291 we have written L<Any::Moose> which will act as Mouse unless Moose is loaded,
292 in which case it will act as Moose.
296 Please don't copy MooseX code to MouseX. If you need extensions, you really
297 should upgrade to Moose. We don't need two parallel sets of extensions!
299 If you really must write a Mouse extension, please contact the Moose mailing
300 list or #moose on IRC beforehand.
304 =head2 meta -> Mouse::Meta::Class
306 Returns this class' metaclass instance.
308 =head2 extends superclasses
310 Sets this class' superclasses.
312 =head2 before (method|methods) => Code
314 Installs a "before" method modifier. See L<Moose/before> or
315 L<Class::Method::Modifiers/before>.
317 Use of this feature requires L<Class::Method::Modifiers>!
319 =head2 after (method|methods) => Code
321 Installs an "after" method modifier. See L<Moose/after> or
322 L<Class::Method::Modifiers/after>.
324 Use of this feature requires L<Class::Method::Modifiers>!
326 =head2 around (method|methods) => Code
328 Installs an "around" method modifier. See L<Moose/around> or
329 L<Class::Method::Modifiers/around>.
331 Use of this feature requires L<Class::Method::Modifiers>!
333 =head2 has (name|names) => parameters
335 Adds an attribute (or if passed an arrayref of names, multiple attributes) to
342 If specified, inlines a read-only/read-write accessor with the same name as
345 =item isa => TypeConstraint
347 Provides type checking in the constructor and accessor. The following types are
348 supported. Any unknown type is taken to be a class check (e.g. isa =>
349 'DateTime' would accept only L<DateTime> objects).
351 Any Item Bool Undef Defined Value Num Int Str ClassName
352 Ref ScalarRef ArrayRef HashRef CodeRef RegexpRef GlobRef
355 For more documentation on type constraints, see L<Mouse::Util::TypeConstraints>.
358 =item required => 0|1
360 Whether this attribute is required to have a value. If the attribute is lazy or
361 has a builder, then providing a value for the attribute in the constructor is
364 =item init_arg => Str | Undef
366 Allows you to use a different key name in the constructor. If undef, the
367 attribue can't be passed to the constructor.
369 =item default => Value | CodeRef
371 Sets the default value of the attribute. If the default is a coderef, it will
372 be invoked to get the default value. Due to quirks of Perl, any bare reference
373 is forbidden, you must wrap the reference in a coderef. Otherwise, all
374 instances will share the same reference.
378 If specified, the default is calculated on demand instead of in the
381 =item predicate => Str
383 Lets you specify a method name for installing a predicate method, which checks
384 that the attribute has a value. It will not invoke a lazy default or builder
389 Lets you specify a method name for installing a clearer method, which clears
390 the attribute's value from the instance. On the next read, lazy or builder will
393 =item handles => HashRef|ArrayRef
395 Lets you specify methods to delegate to the attribute. ArrayRef forwards the
396 given method names to method calls on the attribute. HashRef maps local method
397 names to remote method names called on the attribute. Other forms of
398 L</handles>, such as regular expression and coderef, are not yet supported.
400 =item weak_ref => 0|1
402 Lets you automatically weaken any reference stored in the attribute.
404 Use of this feature requires L<Scalar::Util>!
406 =item trigger => CodeRef
408 Any time the attribute's value is set (either through the accessor or the constructor), the trigger is called on it. The trigger receives as arguments the instance, the new value, and the attribute instance.
410 Mouse 0.05 supported more complex triggers, but this behavior is now removed.
414 Defines a method name to be called to provide the default value of the
415 attribute. C<< builder => 'build_foo' >> is mostly equivalent to
416 C<< default => sub { $_[0]->build_foo } >>.
418 =item auto_deref => 0|1
420 Allows you to automatically dereference ArrayRef and HashRef attributes in list
421 context. In scalar context, the reference is returned (NOT the list length or
422 bucket status). You must specify an appropriate type constraint to use
425 =item lazy_build => 0|1
427 Automatically define lazy => 1 as well as builder => "_build_$attr", clearer =>
428 "clear_$attr', predicate => 'has_$attr' unless they are already defined.
432 =head2 confess error -> BOOM
434 L<Carp/confess> for your convenience.
436 =head2 blessed value -> ClassName | undef
438 L<Scalar::Util/blessed> for your convenience.
444 Importing Mouse will default your class' superclass list to L<Mouse::Object>.
445 You may use L</extends> to replace the superclass list.
449 Please unimport Mouse (C<no Mouse>) so that if someone calls one of the
450 keywords (such as L</extends>) it will break loudly instead breaking subtly.
454 =head2 load_class Class::Name
456 This will load a given C<Class::Name> (or die if it's not loadable).
457 This function can be used in place of tricks like
458 C<eval "use $module"> or using C<require>.
460 =head2 is_class_loaded Class::Name -> Bool
462 Returns whether this class is actually loaded or not. It uses a heuristic which
463 involves checking for the existence of C<$VERSION>, C<@ISA>, and any
464 locally-defined method.
466 =head1 SOURCE CODE ACCESS
468 We have a public git repo:
470 git clone git://jules.scsys.co.uk/gitmo/Mouse.git
474 Shawn M Moore, C<< <sartak at gmail.com> >>
476 Yuval Kogman, C<< <nothingmuch at woobling.org> >>
484 with plenty of code borrowed from L<Class::MOP> and L<Moose>
488 There is a known issue with Mouse on 5.6.2 regarding the @ISA tests. Until
489 this is resolve the minimum version of Perl for Mouse is set to 5.8.0. Patches
490 to resolve these tests are more than welcome.
492 Please report any bugs through RT: email
493 C<bug-mouse at rt.cpan.org>, or browse
494 L<http://rt.cpan.org/NoAuth/ReportBug.html?Queue=Mouse>.
496 =head1 COPYRIGHT AND LICENSE
498 Copyright 2008 Shawn M Moore.
500 This program is free software; you can redistribute it and/or modify it
501 under the same terms as Perl itself.