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 $meta->superclasses;
119 no warnings 'redefine';
120 *{$caller.'::meta'} = sub { $meta };
123 __PACKAGE__->export_to_level( $level+1, $class, @_);
125 # shortcut for the common case of no type character
127 for my $keyword (@EXPORT) {
128 *{ $caller . '::' . $keyword } = *{__PACKAGE__ . '::' . $keyword};
137 for my $keyword (@EXPORT) {
138 delete ${ $caller . '::' }{$keyword};
145 if (ref($class) || !defined($class) || !length($class)) {
146 my $display = defined($class) ? $class : 'undef';
147 confess "Invalid class name ($display)";
150 return 1 if $class eq 'Mouse::Object';
151 return 1 if is_class_loaded($class);
153 (my $file = "$class.pm") =~ s{::}{/}g;
155 eval { CORE::require($file) };
156 confess "Could not load class ($class) because : $@" if $@;
161 sub is_class_loaded {
164 return 0 if ref($class) || !defined($class) || !length($class);
166 # walk the symbol table tree to avoid autovififying
167 # \*{${main::}{"Foo::"}} == \*main::Foo::
170 foreach my $part (split('::', $class)) {
171 return 0 unless exists ${$$pack}{"${part}::"};
172 $pack = \*{${$$pack}{"${part}::"}};
175 # check for $VERSION or @ISA
176 return 1 if exists ${$$pack}{VERSION}
177 && defined *{${$$pack}{VERSION}}{SCALAR};
178 return 1 if exists ${$$pack}{ISA}
179 && defined *{${$$pack}{ISA}}{ARRAY};
181 # check for any method
182 foreach ( keys %{$$pack} ) {
183 next if substr($_, -2, 2) eq '::';
184 return 1 if defined *{${$$pack}{$_}}{CODE};
197 Mouse - Moose minus the antlers
202 use Mouse; # automatically turns on strict and warnings
204 has 'x' => (is => 'rw', isa => 'Int');
205 has 'y' => (is => 'rw', isa => 'Int');
218 has 'z' => (is => 'rw', isa => 'Int');
220 after 'clear' => sub {
227 L<Moose> is wonderful.
229 Unfortunately, it's a little slow. Though significant progress has been made
230 over the years, the compile time penalty is a non-starter for some
233 Mouse aims to alleviate this by providing a subset of Moose's
234 functionality, faster. In particular, L<Moose/has> is missing only a few
235 expert-level features.
237 We're also going as light on dependencies as possible.
238 L<Class::Method::Modifiers> or L<Data::Util> is required if you want support
239 for L</before>, L</after>, and L</around>.
243 Compatibility with Moose has been the utmost concern. Fewer than 1% of the
244 tests fail when run against Moose instead of Mouse. Mouse code coverage is also
245 over 96%. Even the error messages are taken from Moose. The Mouse code just
246 runs the test suite 4x faster.
248 The idea is that, if you need the extra power, you should be able to run
249 C<s/Mouse/Moose/g> on your codebase and have nothing break. To that end,
250 nothingmuch has written L<Squirrel> (part of this distribution) which will act
251 as Mouse unless Moose is loaded, in which case it will act as Moose.
252 L<Any::Moose> is a more high-tech L<Squirrel>.
256 Please don't copy MooseX code to MouseX. If you need extensions, you really
257 should upgrade to Moose. We don't need two parallel sets of extensions!
259 If you really must write a Mouse extension, please contact the Moose mailing
260 list or #moose on IRC beforehand.
264 =head2 meta -> Mouse::Meta::Class
266 Returns this class' metaclass instance.
268 =head2 extends superclasses
270 Sets this class' superclasses.
272 =head2 before (method|methods) => Code
274 Installs a "before" method modifier. See L<Moose/before> or
275 L<Class::Method::Modifiers/before>.
277 Use of this feature requires L<Class::Method::Modifiers>!
279 =head2 after (method|methods) => Code
281 Installs an "after" method modifier. See L<Moose/after> or
282 L<Class::Method::Modifiers/after>.
284 Use of this feature requires L<Class::Method::Modifiers>!
286 =head2 around (method|methods) => Code
288 Installs an "around" method modifier. See L<Moose/around> or
289 L<Class::Method::Modifiers/around>.
291 Use of this feature requires L<Class::Method::Modifiers>!
293 =head2 has (name|names) => parameters
295 Adds an attribute (or if passed an arrayref of names, multiple attributes) to
302 If specified, inlines a read-only/read-write accessor with the same name as
305 =item isa => TypeConstraint
307 Provides basic type checking in the constructor and accessor. Basic types such
308 as C<Int>, C<ArrayRef>, C<Defined> are supported. Any unknown type is taken to
309 be a class check (e.g. isa => 'DateTime' would accept only L<DateTime>
312 =item required => 0|1
314 Whether this attribute is required to have a value. If the attribute is lazy or
315 has a builder, then providing a value for the attribute in the constructor is
318 =item init_arg => Str | Undef
320 Allows you to use a different key name in the constructor. If undef, the
321 attribue can't be passed to the constructor.
323 =item default => Value | CodeRef
325 Sets the default value of the attribute. If the default is a coderef, it will
326 be invoked to get the default value. Due to quirks of Perl, any bare reference
327 is forbidden, you must wrap the reference in a coderef. Otherwise, all
328 instances will share the same reference.
332 If specified, the default is calculated on demand instead of in the
335 =item predicate => Str
337 Lets you specify a method name for installing a predicate method, which checks
338 that the attribute has a value. It will not invoke a lazy default or builder
343 Lets you specify a method name for installing a clearer method, which clears
344 the attribute's value from the instance. On the next read, lazy or builder will
347 =item handles => HashRef|ArrayRef
349 Lets you specify methods to delegate to the attribute. ArrayRef forwards the
350 given method names to method calls on the attribute. HashRef maps local method
351 names to remote method names called on the attribute. Other forms of
352 L</handles>, such as regular expression and coderef, are not yet supported.
354 =item weak_ref => 0|1
356 Lets you automatically weaken any reference stored in the attribute.
358 Use of this feature requires L<Scalar::Util>!
360 =item trigger => CodeRef
362 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.
364 Mouse 0.05 supported more complex triggers, but this behavior is now removed.
368 Defines a method name to be called to provide the default value of the
369 attribute. C<< builder => 'build_foo' >> is mostly equivalent to
370 C<< default => sub { $_[0]->build_foo } >>.
372 =item auto_deref => 0|1
374 Allows you to automatically dereference ArrayRef and HashRef attributes in list
375 context. In scalar context, the reference is returned (NOT the list length or
376 bucket status). You must specify an appropriate type constraint to use
379 =item lazy_build => 0|1
381 Automatically define lazy => 1 as well as builder => "_build_$attr", clearer =>
382 "clear_$attr', predicate => 'has_$attr' unless they are already defined.
386 =head2 confess error -> BOOM
388 L<Carp/confess> for your convenience.
390 =head2 blessed value -> ClassName | undef
392 L<Scalar::Util/blessed> for your convenience.
398 Importing Mouse will default your class' superclass list to L<Mouse::Object>.
399 You may use L</extends> to replace the superclass list.
403 Please unimport Mouse (C<no Mouse>) so that if someone calls one of the
404 keywords (such as L</extends>) it will break loudly instead breaking subtly.
408 =head2 load_class Class::Name
410 This will load a given C<Class::Name> (or die if it's not loadable).
411 This function can be used in place of tricks like
412 C<eval "use $module"> or using C<require>.
414 =head2 is_class_loaded Class::Name -> Bool
416 Returns whether this class is actually loaded or not. It uses a heuristic which
417 involves checking for the existence of C<$VERSION>, C<@ISA>, and any
418 locally-defined method.
422 Shawn M Moore, C<< <sartak at gmail.com> >>
424 Yuval Kogman, C<< <nothingmuch at woobling.org> >>
430 with plenty of code borrowed from L<Class::MOP> and L<Moose>
436 Please report any bugs through RT: email
437 C<bug-mouse at rt.cpan.org>, or browse
438 L<http://rt.cpan.org/NoAuth/ReportBug.html?Queue=Mouse>.
440 =head1 COPYRIGHT AND LICENSE
442 Copyright 2008 Shawn M Moore.
444 This program is free software; you can redistribute it and/or modify it
445 under the same terms as Perl itself.