10 if ($ENV{MOUSE_DEBUG}) {
18 use Scalar::Util 'blessed';
21 use Mouse::Meta::Attribute;
22 use Mouse::Meta::Class;
24 use Mouse::TypeRegistry;
26 our @EXPORT = qw(extends has before after around blessed confess with);
28 sub extends { Mouse::Meta::Class->initialize(caller)->superclasses(@_) }
31 my $meta = Mouse::Meta::Class->initialize(caller);
34 $names = [$names] if !ref($names);
36 for my $name (@$names) {
37 if ($name =~ s/^\+//) {
38 Mouse::Meta::Attribute->clone_parent($meta, $name, @_);
41 Mouse::Meta::Attribute->create($meta, $name, @_);
47 my $meta = Mouse::Meta::Class->initialize(caller);
52 $meta->add_before_method_modifier($_ => $code);
57 my $meta = Mouse::Meta::Class->initialize(caller);
62 $meta->add_after_method_modifier($_ => $code);
67 my $meta = Mouse::Meta::Class->initialize(caller);
72 $meta->add_around_method_modifier($_ => $code);
77 Mouse::Util::apply_all_roles((caller)[0], @_);
88 my $meta = Mouse::Meta::Class->initialize($caller);
89 $meta->superclasses('Mouse::Object')
90 unless $meta->superclasses;
93 no warnings 'redefine';
94 *{$caller.'::meta'} = sub { $meta };
97 __PACKAGE__->export_to_level( 1, $class, @_);
99 # shortcut for the common case of no type character
101 for my $keyword (@EXPORT) {
102 *{ $caller . '::' . $keyword } = *{__PACKAGE__ . '::' . $keyword};
111 for my $keyword (@EXPORT) {
112 delete ${ $caller . '::' }{$keyword};
119 if (ref($class) || !defined($class) || !length($class)) {
120 my $display = defined($class) ? $class : 'undef';
121 confess "Invalid class name ($display)";
124 return 1 if $class eq 'Mouse::Object';
125 return 1 if is_class_loaded($class);
127 (my $file = "$class.pm") =~ s{::}{/}g;
129 eval { CORE::require($file) };
130 confess "Could not load class ($class) because : $@" if $@;
135 sub is_class_loaded {
138 return 0 if ref($class) || !defined($class) || !length($class);
140 # walk the symbol table tree to avoid autovififying
141 # \*{${main::}{"Foo::"}} == \*main::Foo::
144 foreach my $part (split('::', $class)) {
145 return 0 unless exists ${$$pack}{"${part}::"};
146 $pack = \*{${$$pack}{"${part}::"}};
149 # check for $VERSION or @ISA
150 return 1 if exists ${$$pack}{VERSION}
151 && defined *{${$$pack}{VERSION}}{SCALAR};
152 return 1 if exists ${$$pack}{ISA}
153 && defined *{${$$pack}{ISA}}{ARRAY};
155 # check for any method
156 foreach ( keys %{$$pack} ) {
157 next if substr($_, -2, 2) eq '::';
158 return 1 if defined *{${$$pack}{$_}}{CODE};
171 Mouse - Moose minus the antlers
176 use Mouse; # automatically turns on strict and warnings
178 has 'x' => (is => 'rw', isa => 'Int');
179 has 'y' => (is => 'rw', isa => 'Int');
192 has 'z' => (is => 'rw', isa => 'Int');
194 after 'clear' => sub {
201 L<Moose> is wonderful.
203 Unfortunately, it's a little slow. Though significant progress has been made
204 over the years, the compile time penalty is a non-starter for some
207 Mouse aims to alleviate this by providing a subset of Moose's
208 functionality, faster. In particular, L<Moose/has> is missing only a few
209 expert-level features.
211 We're also going as light on dependencies as possible. Most functions we use
212 from L<Scalar::Util> are copied into this dist. L<Scalar::Util> is required if
213 you'd like weak references; there's simply no way to do it from pure Perl.
214 L<Class::Method::Modifiers> is required if you want support for L</before>,
215 L</after>, and L</around>.
219 Compatibility with Moose has been the utmost concern. Fewer than 1% of the
220 tests fail when run against Moose instead of Mouse. Mouse code coverage is also
221 over 96%. Even the error messages are taken from Moose. The Mouse code just
222 runs the test suite 4x faster.
224 The idea is that, if you need the extra power, you should be able to run
225 C<s/Mouse/Moose/g> on your codebase and have nothing break. To that end,
226 nothingmuch has written L<Squirrel> (part of this distribution) which will act
227 as Mouse unless Moose is loaded, in which case it will act as Moose.
229 Mouse also has the blessings of Moose's author, stevan.
233 =head2 meta -> Mouse::Meta::Class
235 Returns this class' metaclass instance.
237 =head2 extends superclasses
239 Sets this class' superclasses.
241 =head2 before (method|methods) => Code
243 Installs a "before" method modifier. See L<Moose/before> or
244 L<Class::Method::Modifiers/before>.
246 Use of this feature requires L<Class::Method::Modifiers>!
248 =head2 after (method|methods) => Code
250 Installs an "after" method modifier. See L<Moose/after> or
251 L<Class::Method::Modifiers/after>.
253 Use of this feature requires L<Class::Method::Modifiers>!
255 =head2 around (method|methods) => Code
257 Installs an "around" method modifier. See L<Moose/around> or
258 L<Class::Method::Modifiers/around>.
260 Use of this feature requires L<Class::Method::Modifiers>!
262 =head2 has (name|names) => parameters
264 Adds an attribute (or if passed an arrayref of names, multiple attributes) to
271 If specified, inlines a read-only/read-write accessor with the same name as
274 =item isa => TypeConstraint
276 Provides basic type checking in the constructor and accessor. Basic types such
277 as C<Int>, C<ArrayRef>, C<Defined> are supported. Any unknown type is taken to
278 be a class check (e.g. isa => 'DateTime' would accept only L<DateTime>
281 =item required => 0|1
283 Whether this attribute is required to have a value. If the attribute is lazy or
284 has a builder, then providing a value for the attribute in the constructor is
287 =item init_arg => Str | Undef
289 Allows you to use a different key name in the constructor. If undef, the
290 attribue can't be passed to the constructor.
292 =item default => Value | CodeRef
294 Sets the default value of the attribute. If the default is a coderef, it will
295 be invoked to get the default value. Due to quirks of Perl, any bare reference
296 is forbidden, you must wrap the reference in a coderef. Otherwise, all
297 instances will share the same reference.
301 If specified, the default is calculated on demand instead of in the
304 =item predicate => Str
306 Lets you specify a method name for installing a predicate method, which checks
307 that the attribute has a value. It will not invoke a lazy default or builder
312 Lets you specify a method name for installing a clearer method, which clears
313 the attribute's value from the instance. On the next read, lazy or builder will
316 =item handles => HashRef|ArrayRef
318 Lets you specify methods to delegate to the attribute. ArrayRef forwards the
319 given method names to method calls on the attribute. HashRef maps local method
320 names to remote method names called on the attribute. Other forms of
321 L</handles>, such as regular expression and coderef, are not yet supported.
323 =item weak_ref => 0|1
325 Lets you automatically weaken any reference stored in the attribute.
327 Use of this feature requires L<Scalar::Util>!
329 =item trigger => CodeRef
331 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.
333 Mouse 0.05 supported more complex triggers, but this behavior is now removed.
337 Defines a method name to be called to provide the default value of the
338 attribute. C<< builder => 'build_foo' >> is mostly equivalent to
339 C<< default => sub { $_[0]->build_foo } >>.
341 =item auto_deref => 0|1
343 Allows you to automatically dereference ArrayRef and HashRef attributes in list
344 context. In scalar context, the reference is returned (NOT the list length or
345 bucket status). You must specify an appropriate type constraint to use
348 =item lazy_build => 0|1
350 Automatically define lazy => 1 as well as builder => "_build_$attr", clearer =>
351 "clear_$attr', predicate => 'has_$attr' unless they are already defined.
355 =head2 confess error -> BOOM
357 L<Carp/confess> for your convenience.
359 =head2 blessed value -> ClassName | undef
361 L<Scalar::Util/blessed> for your convenience.
367 Importing Mouse will default your class' superclass list to L<Mouse::Object>.
368 You may use L</extends> to replace the superclass list.
372 Please unimport Mouse (C<no Mouse>) so that if someone calls one of the
373 keywords (such as L</extends>) it will break loudly instead breaking subtly.
377 =head2 load_class Class::Name
379 This will load a given C<Class::Name> (or die if it's not loadable).
380 This function can be used in place of tricks like
381 C<eval "use $module"> or using C<require>.
383 =head2 is_class_loaded Class::Name -> Bool
385 Returns whether this class is actually loaded or not. It uses a heuristic which
386 involves checking for the existence of C<$VERSION>, C<@ISA>, and any
387 locally-defined method.
391 Shawn M Moore, C<< <sartak at gmail.com> >>
393 Yuval Kogman, C<< <nothingmuch at woobling.org> >>
399 with plenty of code borrowed from L<Class::MOP> and L<Moose>
405 Please report any bugs through RT: email
406 C<bug-mouse at rt.cpan.org>, or browse
407 L<http://rt.cpan.org/NoAuth/ReportBug.html?Queue=Mouse>.
409 =head1 COPYRIGHT AND LICENSE
411 Copyright 2008 Shawn M Moore.
413 This program is free software; you can redistribute it and/or modify it
414 under the same terms as Perl itself.