11 use Scalar::Util 'blessed';
12 use Class::Method::Modifiers ();
14 use Mouse::Meta::Attribute;
15 use Mouse::Meta::Class;
17 use Mouse::TypeRegistry;
24 my $meta = Mouse::Meta::Class->initialize($CALLER);
31 $caller->meta->superclasses(@_);
39 $names = [$names] if !ref($names);
41 for my $name (@$names) {
42 Mouse::Meta::Attribute->create($package, $name, @_);
56 return \&Class::Method::Modifiers::before;
60 return \&Class::Method::Modifiers::after;
64 return \&Class::Method::Modifiers::around;
68 my $exporter = Sub::Exporter::build_exporter({
70 groups => { default => [':all'] },
79 my $meta = Mouse::Meta::Class->initialize($CALLER);
80 $meta->superclasses('Mouse::Object')
81 unless $meta->superclasses;
90 for my $keyword (keys %exports) {
91 next if $keyword eq 'meta'; # we don't delete this one
92 delete ${ $caller . '::' }{$keyword};
100 if (ref($class) || !defined($class) || !length($class)) {
101 my $display = defined($class) ? $class : 'undef';
102 confess "Invalid class name ($display)";
105 return 1 if is_class_loaded($class);
107 (my $file = "$class.pm") =~ s{::}{/}g;
109 eval { CORE::require($file) };
110 confess "Could not load class ($class) because : $@" if $@;
115 sub is_class_loaded {
118 return 0 if ref($class) || !defined($class) || !length($class);
120 # walk the symbol table tree to avoid autovififying
121 # \*{${main::}{"Foo::"}} == \*main::Foo::
124 foreach my $part (split('::', $class)) {
125 return 0 unless exists ${$$pack}{"${part}::"};
126 $pack = \*{${$$pack}{"${part}::"}};
129 # check for $VERSION or @ISA
130 return 1 if exists ${$$pack}{VERSION}
131 && defined *{${$$pack}{VERSION}}{SCALAR};
132 return 1 if exists ${$$pack}{ISA}
133 && defined *{${$$pack}{ISA}}{ARRAY};
135 # check for any method
136 foreach ( keys %{$$pack} ) {
137 next if substr($_, -2, 2) eq '::';
138 return 1 if defined *{${$$pack}{$_}}{CODE};
151 Mouse - Moose minus the antlers
156 use Mouse; # automatically turns on strict and warnings
158 has 'x' => (is => 'rw', isa => 'Int');
159 has 'y' => (is => 'rw', isa => 'Int');
172 has 'z' => (is => 'rw', isa => 'Int');
174 after 'clear' => sub {
181 L<Moose> is wonderful.
183 Unfortunately, it's a little slow. Though significant progress has been made
184 over the years, the compile time penalty is a non-starter for some
187 Mouse aims to alleviate this by providing a subset of Moose's
188 functionality, faster. In particular, L<Moose/has> is missing only a few
189 expert-level features.
193 Compatibility with Moose has been the utmost concern. Fewer than 1% of the
194 tests fail when run against Moose instead of Mouse. Mouse code coverage is also
195 over 99%. Even the error messages are taken from Moose. The Mouse code just
196 runs the test suite 3x-4x faster.
198 The idea is that, if you need the extra power, you should be able to run
199 C<s/Mouse/Moose/g> on your codebase and have nothing break. To that end,
200 nothingmuch has written L<Squirrel> (part of this distribution) which will act
201 as Mouse unless Moose is loaded, in which case it will act as Moose.
203 Mouse also has the blessings of Moose's author, stevan.
205 =head2 MISSING FEATURES
209 Fixing this one slightly less soon. stevan has suggested an implementation
210 strategy. Mouse currently mostly ignores methods.
214 User-defined type constraints and parameterized types may be implemented. Type
215 coercions probably not (patches welcome).
217 =head3 Bootstrapped meta world
219 Very handy for extensions to the MOP. Not pressing, but would be nice to have.
221 =head3 Modification of attribute metaclass
223 When you declare an attribute with L</has>, you get the inlined accessors
224 installed immediately. Modifying the attribute metaclass, even if possible,
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 =head2 after (method|methods) => Code
248 Installs an "after" method modifier. See L<Moose/after> or
249 L<Class::Method::Modifiers/after>.
251 =head2 around (method|methods) => Code
253 Installs an "around" method modifier. See L<Moose/around> or
254 L<Class::Method::Modifiers/around>.
256 =head2 has (name|names) => parameters
258 Adds an attribute (or if passed an arrayref of names, multiple attributes) to
265 If specified, inlines a read-only/read-write accessor with the same name as
268 =item isa => TypeConstraint
270 Provides basic type checking in the constructor and accessor. Basic types such
271 as C<Int>, C<ArrayRef>, C<Defined> are supported. Any unknown type is taken to
272 be a class check (e.g. isa => 'DateTime' would accept only L<DateTime>
275 =item required => 0|1
277 Whether this attribute is required to have a value. If the attribute is lazy or
278 has a builder, then providing a value for the attribute in the constructor is
281 =item init_arg => Str
283 Allows you to use a different key name in the constructor.
285 =item default => Value | CodeRef
287 Sets the default value of the attribute. If the default is a coderef, it will
288 be invoked to get the default value. Due to quirks of Perl, any bare reference
289 is forbidden, you must wrap the reference in a coderef. Otherwise, all
290 instances will share the same reference.
294 If specified, the default is calculated on demand instead of in the
297 =item predicate => Str
299 Lets you specify a method name for installing a predicate method, which checks
300 that the attribute has a value. It will not invoke a lazy default or builder
305 Lets you specify a method name for installing a clearer method, which clears
306 the attribute's value from the instance. On the next read, lazy or builder will
309 =item handles => HashRef|ArrayRef
311 Lets you specify methods to delegate to the attribute. ArrayRef forwards the
312 given method names to method calls on the attribute. HashRef maps local method
313 names to remote method names called on the attribute. Other forms of
314 L</handles>, such as regular expression and coderef, are not yet supported.
316 =item weak_ref => 0|1
318 Lets you automatically weaken any reference stored in the attribute.
320 =item trigger => Coderef
322 Any time the attribute's value is set (either through the accessor or the
323 constructor), the trigger is called on it. The trigger receives as arguments
324 the instance, the new value, and the attribute instance.
328 Defines a method name to be called to provide the default value of the
329 attribute. C<< builder => 'build_foo' >> is mostly equivalent to
330 C<< default => sub { $_[0]->build_foo } >>.
332 =item auto_deref => 0|1
334 Allows you to automatically dereference ArrayRef and HashRef attributes in list
335 context. In scalar context, the reference is returned (NOT the list length or
336 bucket status). You must specify an appropriate type constraint to use
341 =head2 confess error -> BOOM
343 L<Carp/confess> for your convenience.
345 =head2 blessed value -> ClassName | undef
347 L<Scalar::Util/blessed> for your convenience.
353 Importing Mouse will default your class' superclass list to L<Mouse::Object>.
354 You may use L</extends> to replace the superclass list.
358 Please unimport Mouse (C<no Mouse>) so that if someone calls one of the
359 keywords (such as L</extends>) it will break loudly instead breaking subtly.
363 =head2 load_class Class::Name
365 This will load a given C<Class::Name> (or die if it's not loadable).
366 This function can be used in place of tricks like
367 C<eval "use $module"> or using C<require>.
369 =head2 is_class_loaded Class::Name -> Bool
371 Returns whether this class is actually loaded or not. It uses a heuristic which
372 involves checking for the existence of C<$VERSION>, C<@ISA>, and any
373 locally-defined method.
377 Shawn M Moore, C<< <sartak at gmail.com> >>
379 with plenty of code borrowed from L<Class::MOP> and L<Moose>
385 Please report any bugs through RT: email
386 C<bug-mouse at rt.cpan.org>, or browse
387 L<http://rt.cpan.org/NoAuth/ReportBug.html?Queue=Mouse>.
389 =head1 COPYRIGHT AND LICENSE
391 Copyright 2008 Shawn M Moore.
393 This program is free software; you can redistribute it and/or modify it
394 under the same terms as Perl itself.