10 if ($ENV{MOUSE_DEBUG}) {
18 use Scalar::Util 'blessed';
21 use Mouse::Meta::Attribute;
22 use Mouse::Meta::Class;
24 use Mouse::Util::TypeConstraints;
26 our @EXPORT = qw(extends has before after around override super 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], @_);
85 # This check avoids a recursion loop - see
86 # t/100_bugs/020_super_recursion.t
87 return if defined $SUPER_PACKAGE && $SUPER_PACKAGE ne caller();
88 return unless $SUPER_BODY; $SUPER_BODY->(@SUPER_ARGS);
92 my $meta = Mouse::Meta::Class->initialize(caller);
93 my $pkg = $meta->name;
98 my $body = $pkg->can($name)
99 or confess "You cannot override '$name' because it has no super method";
101 $meta->add_method($name => sub {
102 local $SUPER_PACKAGE = $pkg;
103 local @SUPER_ARGS = @_;
104 local $SUPER_BODY = $body;
118 # we should never export to main
119 if ($caller eq 'main') {
120 warn qq{$class does not export its sugar to the 'main' package.\n};
124 my $meta = Mouse::Meta::Class->initialize($caller);
125 $meta->superclasses('Mouse::Object')
126 unless $meta->superclasses;
129 no warnings 'redefine';
130 *{$caller.'::meta'} = sub { $meta };
133 __PACKAGE__->export_to_level( 1, $class, @_);
135 # shortcut for the common case of no type character
137 for my $keyword (@EXPORT) {
138 *{ $caller . '::' . $keyword } = *{__PACKAGE__ . '::' . $keyword};
147 for my $keyword (@EXPORT) {
148 delete ${ $caller . '::' }{$keyword};
155 if (ref($class) || !defined($class) || !length($class)) {
156 my $display = defined($class) ? $class : 'undef';
157 confess "Invalid class name ($display)";
160 return 1 if $class eq 'Mouse::Object';
161 return 1 if is_class_loaded($class);
163 (my $file = "$class.pm") =~ s{::}{/}g;
165 eval { CORE::require($file) };
166 confess "Could not load class ($class) because : $@" if $@;
171 sub is_class_loaded {
174 return 0 if ref($class) || !defined($class) || !length($class);
176 # walk the symbol table tree to avoid autovififying
177 # \*{${main::}{"Foo::"}} == \*main::Foo::
180 foreach my $part (split('::', $class)) {
181 return 0 unless exists ${$$pack}{"${part}::"};
182 $pack = \*{${$$pack}{"${part}::"}};
185 # check for $VERSION or @ISA
186 return 1 if exists ${$$pack}{VERSION}
187 && defined *{${$$pack}{VERSION}}{SCALAR};
188 return 1 if exists ${$$pack}{ISA}
189 && defined *{${$$pack}{ISA}}{ARRAY};
191 # check for any method
192 foreach ( keys %{$$pack} ) {
193 next if substr($_, -2, 2) eq '::';
194 return 1 if defined *{${$$pack}{$_}}{CODE};
207 Mouse - Moose minus the antlers
212 use Mouse; # automatically turns on strict and warnings
214 has 'x' => (is => 'rw', isa => 'Int');
215 has 'y' => (is => 'rw', isa => 'Int');
228 has 'z' => (is => 'rw', isa => 'Int');
230 after 'clear' => sub {
237 L<Moose> is wonderful.
239 Unfortunately, it's a little slow. Though significant progress has been made
240 over the years, the compile time penalty is a non-starter for some
243 Mouse aims to alleviate this by providing a subset of Moose's
244 functionality, faster. In particular, L<Moose/has> is missing only a few
245 expert-level features.
247 We're also going as light on dependencies as possible.
248 L<Class::Method::Modifiers> or L<Data::Util> is required if you want support
249 for L</before>, L</after>, and L</around>.
253 Compatibility with Moose has been the utmost concern. Fewer than 1% of the
254 tests fail when run against Moose instead of Mouse. Mouse code coverage is also
255 over 96%. Even the error messages are taken from Moose. The Mouse code just
256 runs the test suite 4x faster.
258 The idea is that, if you need the extra power, you should be able to run
259 C<s/Mouse/Moose/g> on your codebase and have nothing break. To that end,
260 nothingmuch has written L<Squirrel> (part of this distribution) which will act
261 as Mouse unless Moose is loaded, in which case it will act as Moose.
262 L<Any::Moose> is a more high-tech L<Squirrel>.
266 Please don't copy MooseX code to MouseX. If you need extensions, you really
267 should upgrade to Moose. We don't need two parallel sets of extensions!
269 If you really must write a Mouse extension, please contact the Moose mailing
270 list or #moose on IRC beforehand.
274 =head2 meta -> Mouse::Meta::Class
276 Returns this class' metaclass instance.
278 =head2 extends superclasses
280 Sets this class' superclasses.
282 =head2 before (method|methods) => Code
284 Installs a "before" method modifier. See L<Moose/before> or
285 L<Class::Method::Modifiers/before>.
287 Use of this feature requires L<Class::Method::Modifiers>!
289 =head2 after (method|methods) => Code
291 Installs an "after" method modifier. See L<Moose/after> or
292 L<Class::Method::Modifiers/after>.
294 Use of this feature requires L<Class::Method::Modifiers>!
296 =head2 around (method|methods) => Code
298 Installs an "around" method modifier. See L<Moose/around> or
299 L<Class::Method::Modifiers/around>.
301 Use of this feature requires L<Class::Method::Modifiers>!
303 =head2 has (name|names) => parameters
305 Adds an attribute (or if passed an arrayref of names, multiple attributes) to
312 If specified, inlines a read-only/read-write accessor with the same name as
315 =item isa => TypeConstraint
317 Provides basic type checking in the constructor and accessor. Basic types such
318 as C<Int>, C<ArrayRef>, C<Defined> are supported. Any unknown type is taken to
319 be a class check (e.g. isa => 'DateTime' would accept only L<DateTime>
322 =item required => 0|1
324 Whether this attribute is required to have a value. If the attribute is lazy or
325 has a builder, then providing a value for the attribute in the constructor is
328 =item init_arg => Str | Undef
330 Allows you to use a different key name in the constructor. If undef, the
331 attribue can't be passed to the constructor.
333 =item default => Value | CodeRef
335 Sets the default value of the attribute. If the default is a coderef, it will
336 be invoked to get the default value. Due to quirks of Perl, any bare reference
337 is forbidden, you must wrap the reference in a coderef. Otherwise, all
338 instances will share the same reference.
342 If specified, the default is calculated on demand instead of in the
345 =item predicate => Str
347 Lets you specify a method name for installing a predicate method, which checks
348 that the attribute has a value. It will not invoke a lazy default or builder
353 Lets you specify a method name for installing a clearer method, which clears
354 the attribute's value from the instance. On the next read, lazy or builder will
357 =item handles => HashRef|ArrayRef
359 Lets you specify methods to delegate to the attribute. ArrayRef forwards the
360 given method names to method calls on the attribute. HashRef maps local method
361 names to remote method names called on the attribute. Other forms of
362 L</handles>, such as regular expression and coderef, are not yet supported.
364 =item weak_ref => 0|1
366 Lets you automatically weaken any reference stored in the attribute.
368 Use of this feature requires L<Scalar::Util>!
370 =item trigger => CodeRef
372 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.
374 Mouse 0.05 supported more complex triggers, but this behavior is now removed.
378 Defines a method name to be called to provide the default value of the
379 attribute. C<< builder => 'build_foo' >> is mostly equivalent to
380 C<< default => sub { $_[0]->build_foo } >>.
382 =item auto_deref => 0|1
384 Allows you to automatically dereference ArrayRef and HashRef attributes in list
385 context. In scalar context, the reference is returned (NOT the list length or
386 bucket status). You must specify an appropriate type constraint to use
389 =item lazy_build => 0|1
391 Automatically define lazy => 1 as well as builder => "_build_$attr", clearer =>
392 "clear_$attr', predicate => 'has_$attr' unless they are already defined.
396 =head2 confess error -> BOOM
398 L<Carp/confess> for your convenience.
400 =head2 blessed value -> ClassName | undef
402 L<Scalar::Util/blessed> for your convenience.
408 Importing Mouse will default your class' superclass list to L<Mouse::Object>.
409 You may use L</extends> to replace the superclass list.
413 Please unimport Mouse (C<no Mouse>) so that if someone calls one of the
414 keywords (such as L</extends>) it will break loudly instead breaking subtly.
418 =head2 load_class Class::Name
420 This will load a given C<Class::Name> (or die if it's not loadable).
421 This function can be used in place of tricks like
422 C<eval "use $module"> or using C<require>.
424 =head2 is_class_loaded Class::Name -> Bool
426 Returns whether this class is actually loaded or not. It uses a heuristic which
427 involves checking for the existence of C<$VERSION>, C<@ISA>, and any
428 locally-defined method.
432 Shawn M Moore, C<< <sartak at gmail.com> >>
434 Yuval Kogman, C<< <nothingmuch at woobling.org> >>
440 with plenty of code borrowed from L<Class::MOP> and L<Moose>
446 Please report any bugs through RT: email
447 C<bug-mouse at rt.cpan.org>, or browse
448 L<http://rt.cpan.org/NoAuth/ReportBug.html?Queue=Mouse>.
450 =head1 COPYRIGHT AND LICENSE
452 Copyright 2008 Shawn M Moore.
454 This program is free software; you can redistribute it and/or modify it
455 under the same terms as Perl itself.