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 = $body;
98 if (ref($_[0]) && ref($_[0]) eq 'HASH') {
104 my $level = delete $opts->{into_level};
105 $level = 0 unless defined $level;
106 my $caller = caller($level);
108 # we should never export to main
109 if ($caller eq 'main') {
110 warn qq{$class does not export its sugar to the 'main' package.\n};
114 my $meta = Mouse::Meta::Class->initialize($caller);
115 $meta->superclasses('Mouse::Object')
116 unless $meta->superclasses;
118 # make a subtype for each Mouse class
119 class_type($caller) unless find_type_constraint($caller);
122 no warnings 'redefine';
123 *{$caller.'::meta'} = sub { $meta };
126 __PACKAGE__->export_to_level( $level+1, $class, @_);
128 # shortcut for the common case of no type character
130 for my $keyword (@EXPORT) {
131 *{ $caller . '::' . $keyword } = *{__PACKAGE__ . '::' . $keyword};
140 for my $keyword (@EXPORT) {
141 delete ${ $caller . '::' }{$keyword};
148 if (ref($class) || !defined($class) || !length($class)) {
149 my $display = defined($class) ? $class : 'undef';
150 confess "Invalid class name ($display)";
153 return 1 if $class eq 'Mouse::Object';
154 return 1 if is_class_loaded($class);
156 (my $file = "$class.pm") =~ s{::}{/}g;
158 eval { CORE::require($file) };
159 confess "Could not load class ($class) because : $@" if $@;
164 sub is_class_loaded {
167 return 0 if ref($class) || !defined($class) || !length($class);
169 # walk the symbol table tree to avoid autovififying
170 # \*{${main::}{"Foo::"}} == \*main::Foo::
173 foreach my $part (split('::', $class)) {
174 return 0 unless exists ${$$pack}{"${part}::"};
175 $pack = \*{${$$pack}{"${part}::"}};
178 # check for $VERSION or @ISA
179 return 1 if exists ${$$pack}{VERSION}
180 && defined *{${$$pack}{VERSION}}{SCALAR};
181 return 1 if exists ${$$pack}{ISA}
182 && defined *{${$$pack}{ISA}}{ARRAY};
184 # check for any method
185 foreach ( keys %{$$pack} ) {
186 next if substr($_, -2, 2) eq '::';
187 return 1 if defined *{${$$pack}{$_}}{CODE};
200 Mouse - Moose minus the antlers
205 use Mouse; # automatically turns on strict and warnings
207 has 'x' => (is => 'rw', isa => 'Int');
208 has 'y' => (is => 'rw', isa => 'Int');
221 has 'z' => (is => 'rw', isa => 'Int');
223 after 'clear' => sub {
230 L<Moose> is wonderful.
232 Unfortunately, it's a little slow. Though significant progress has been made
233 over the years, the compile time penalty is a non-starter for some
236 Mouse aims to alleviate this by providing a subset of Moose's
237 functionality, faster. In particular, L<Moose/has> is missing only a few
238 expert-level features.
240 We're also going as light on dependencies as possible.
241 L<Class::Method::Modifiers> or L<Data::Util> is required if you want support
242 for L</before>, L</after>, and L</around>.
246 Compatibility with Moose has been the utmost concern. Fewer than 1% of the
247 tests fail when run against Moose instead of Mouse. Mouse code coverage is also
248 over 96%. Even the error messages are taken from Moose. The Mouse code just
249 runs the test suite 4x faster.
251 The idea is that, if you need the extra power, you should be able to run
252 C<s/Mouse/Moose/g> on your codebase and have nothing break. To that end,
253 nothingmuch has written L<Squirrel> (part of this distribution) which will act
254 as Mouse unless Moose is loaded, in which case it will act as Moose.
255 L<Any::Moose> is a more high-tech L<Squirrel>.
259 Please don't copy MooseX code to MouseX. If you need extensions, you really
260 should upgrade to Moose. We don't need two parallel sets of extensions!
262 If you really must write a Mouse extension, please contact the Moose mailing
263 list or #moose on IRC beforehand.
267 =head2 meta -> Mouse::Meta::Class
269 Returns this class' metaclass instance.
271 =head2 extends superclasses
273 Sets this class' superclasses.
275 =head2 before (method|methods) => Code
277 Installs a "before" method modifier. See L<Moose/before> or
278 L<Class::Method::Modifiers/before>.
280 Use of this feature requires L<Class::Method::Modifiers>!
282 =head2 after (method|methods) => Code
284 Installs an "after" method modifier. See L<Moose/after> or
285 L<Class::Method::Modifiers/after>.
287 Use of this feature requires L<Class::Method::Modifiers>!
289 =head2 around (method|methods) => Code
291 Installs an "around" method modifier. See L<Moose/around> or
292 L<Class::Method::Modifiers/around>.
294 Use of this feature requires L<Class::Method::Modifiers>!
296 =head2 has (name|names) => parameters
298 Adds an attribute (or if passed an arrayref of names, multiple attributes) to
305 If specified, inlines a read-only/read-write accessor with the same name as
308 =item isa => TypeConstraint
310 Provides basic type checking in the constructor and accessor. Basic types such
311 as C<Int>, C<ArrayRef>, C<Defined> are supported. Any unknown type is taken to
312 be a class check (e.g. isa => 'DateTime' would accept only L<DateTime>
315 =item required => 0|1
317 Whether this attribute is required to have a value. If the attribute is lazy or
318 has a builder, then providing a value for the attribute in the constructor is
321 =item init_arg => Str | Undef
323 Allows you to use a different key name in the constructor. If undef, the
324 attribue can't be passed to the constructor.
326 =item default => Value | CodeRef
328 Sets the default value of the attribute. If the default is a coderef, it will
329 be invoked to get the default value. Due to quirks of Perl, any bare reference
330 is forbidden, you must wrap the reference in a coderef. Otherwise, all
331 instances will share the same reference.
335 If specified, the default is calculated on demand instead of in the
338 =item predicate => Str
340 Lets you specify a method name for installing a predicate method, which checks
341 that the attribute has a value. It will not invoke a lazy default or builder
346 Lets you specify a method name for installing a clearer method, which clears
347 the attribute's value from the instance. On the next read, lazy or builder will
350 =item handles => HashRef|ArrayRef
352 Lets you specify methods to delegate to the attribute. ArrayRef forwards the
353 given method names to method calls on the attribute. HashRef maps local method
354 names to remote method names called on the attribute. Other forms of
355 L</handles>, such as regular expression and coderef, are not yet supported.
357 =item weak_ref => 0|1
359 Lets you automatically weaken any reference stored in the attribute.
361 Use of this feature requires L<Scalar::Util>!
363 =item trigger => CodeRef
365 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.
367 Mouse 0.05 supported more complex triggers, but this behavior is now removed.
371 Defines a method name to be called to provide the default value of the
372 attribute. C<< builder => 'build_foo' >> is mostly equivalent to
373 C<< default => sub { $_[0]->build_foo } >>.
375 =item auto_deref => 0|1
377 Allows you to automatically dereference ArrayRef and HashRef attributes in list
378 context. In scalar context, the reference is returned (NOT the list length or
379 bucket status). You must specify an appropriate type constraint to use
382 =item lazy_build => 0|1
384 Automatically define lazy => 1 as well as builder => "_build_$attr", clearer =>
385 "clear_$attr', predicate => 'has_$attr' unless they are already defined.
389 =head2 confess error -> BOOM
391 L<Carp/confess> for your convenience.
393 =head2 blessed value -> ClassName | undef
395 L<Scalar::Util/blessed> for your convenience.
401 Importing Mouse will default your class' superclass list to L<Mouse::Object>.
402 You may use L</extends> to replace the superclass list.
406 Please unimport Mouse (C<no Mouse>) so that if someone calls one of the
407 keywords (such as L</extends>) it will break loudly instead breaking subtly.
411 =head2 load_class Class::Name
413 This will load a given C<Class::Name> (or die if it's not loadable).
414 This function can be used in place of tricks like
415 C<eval "use $module"> or using C<require>.
417 =head2 is_class_loaded Class::Name -> Bool
419 Returns whether this class is actually loaded or not. It uses a heuristic which
420 involves checking for the existence of C<$VERSION>, C<@ISA>, and any
421 locally-defined method.
425 Shawn M Moore, C<< <sartak at gmail.com> >>
427 Yuval Kogman, C<< <nothingmuch at woobling.org> >>
433 with plenty of code borrowed from L<Class::MOP> and L<Moose>
439 Please report any bugs through RT: email
440 C<bug-mouse at rt.cpan.org>, or browse
441 L<http://rt.cpan.org/NoAuth/ReportBug.html?Queue=Mouse>.
443 =head1 COPYRIGHT AND LICENSE
445 Copyright 2008 Shawn M Moore.
447 This program is free software; you can redistribute it and/or modify it
448 under the same terms as Perl itself.