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
155 Version 0.02 released 11 Jun 08
160 use Mouse; # automatically turns on strict and warnings
162 has 'x' => (is => 'rw', isa => 'Int');
163 has 'y' => (is => 'rw', isa => 'Int');
176 has 'z' => (is => 'rw', isa => 'Int');
178 after 'clear' => sub {
185 L<Moose> is wonderful.
187 Unfortunately, it's a little slow. Though significant progress has been made
188 over the years, the compile time penalty is a non-starter for some
191 Mouse aims to alleviate this by providing a subset of Moose's
192 functionality, faster. In particular, L<Moose/has> is missing only a few
193 expert-level features.
197 Compatibility with Moose has been the utmost concern. Fewer than 1% of the
198 tests fail when run against Moose instead of Mouse. Mouse code coverage is also
199 over 99%. Even the error messages are taken from Moose. The Mouse code just
200 runs the test suite 3x-4x faster.
202 The idea is that, if you need the extra power, you should be able to run
203 C<s/Mouse/Moose/g> on your codebase and have nothing break. To that end,
204 nothingmuch has written L<Squirrel> (part of this distribution) which will act
205 as Mouse unless Moose is loaded, in which case it will act as Moose.
207 Mouse also has the blessings of Moose's author, stevan.
209 =head2 MISSING FEATURES
213 Fixing this one slightly less soon. stevan has suggested an implementation
214 strategy. Mouse currently mostly ignores methods.
218 User-defined type constraints and parameterized types may be implemented. Type
219 coercions probably not (patches welcome).
221 =head3 Bootstrapped meta world
223 Very handy for extensions to the MOP. Not pressing, but would be nice to have.
225 =head3 Modification of attribute metaclass
227 When you declare an attribute with L</has>, you get the inlined accessors
228 installed immediately. Modifying the attribute metaclass, even if possible,
237 =head2 meta -> Mouse::Meta::Class
239 Returns this class' metaclass instance.
241 =head2 extends superclasses
243 Sets this class' superclasses.
245 =head2 before (method|methods) => Code
247 Installs a "before" method modifier. See L<Moose/before> or
248 L<Class::Method::Modifiers/before>.
250 =head2 after (method|methods) => Code
252 Installs an "after" method modifier. See L<Moose/after> or
253 L<Class::Method::Modifiers/after>.
255 =head2 around (method|methods) => Code
257 Installs an "around" method modifier. See L<Moose/around> or
258 L<Class::Method::Modifiers/around>.
260 =head2 has (name|names) => parameters
262 Adds an attribute (or if passed an arrayref of names, multiple attributes) to
269 If specified, inlines a read-only/read-write accessor with the same name as
272 =item isa => TypeConstraint
274 Provides basic type checking in the constructor and accessor. Basic types such
275 as C<Int>, C<ArrayRef>, C<Defined> are supported. Any unknown type is taken to
276 be a class check (e.g. isa => 'DateTime' would accept only L<DateTime>
279 =item required => 0|1
281 Whether this attribute is required to have a value. If the attribute is lazy or
282 has a builder, then providing a value for the attribute in the constructor is
285 =item init_arg => Str
287 Allows you to use a different key name in the constructor.
289 =item default => Value | CodeRef
291 Sets the default value of the attribute. If the default is a coderef, it will
292 be invoked to get the default value. Due to quirks of Perl, any bare reference
293 is forbidden, you must wrap the reference in a coderef. Otherwise, all
294 instances will share the same reference.
298 If specified, the default is calculated on demand instead of in the
301 =item predicate => Str
303 Lets you specify a method name for installing a predicate method, which checks
304 that the attribute has a value. It will not invoke a lazy default or builder
309 Lets you specify a method name for installing a clearer method, which clears
310 the attribute's value from the instance. On the next read, lazy or builder will
313 =item handles => HashRef|ArrayRef
315 Lets you specify methods to delegate to the attribute. ArrayRef forwards the
316 given method names to method calls on the attribute. HashRef maps local method
317 names to remote method names called on the attribute. Other forms of
318 L</handles>, such as regular expression and coderef, are not yet supported.
320 =item weak_ref => 0|1
322 Lets you automatically weaken any reference stored in the attribute.
324 =item trigger => Coderef
326 Any time the attribute's value is set (either through the accessor or the
327 constructor), the trigger is called on it. The trigger receives as arguments
328 the instance, the new value, and the attribute instance.
332 Defines a method name to be called to provide the default value of the
333 attribute. C<< builder => 'build_foo' >> is mostly equivalent to
334 C<< default => sub { $_[0]->build_foo } >>.
336 =item auto_deref => 0|1
338 Allows you to automatically dereference ArrayRef and HashRef attributes in list
339 context. In scalar context, the reference is returned (NOT the list length or
340 bucket status). You must specify an appropriate type constraint to use
345 =head2 confess error -> BOOM
347 L<Carp/confess> for your convenience.
349 =head2 blessed value -> ClassName | undef
351 L<Scalar::Util/blessed> for your convenience.
357 Importing Mouse will default your class' superclass list to L<Mouse::Object>.
358 You may use L</extends> to replace the superclass list.
362 Please unimport Mouse (C<no Mouse>) so that if someone calls one of the
363 keywords (such as L</extends>) it will break loudly instead breaking subtly.
367 =head2 load_class Class::Name
369 This will load a given C<Class::Name> (or die if it's not loadable).
370 This function can be used in place of tricks like
371 C<eval "use $module"> or using C<require>.
373 =head2 is_class_loaded Class::Name -> Bool
375 Returns whether this class is actually loaded or not. It uses a heuristic which
376 involves checking for the existence of C<$VERSION>, C<@ISA>, and any
377 locally-defined method.
381 Shawn M Moore, C<< <sartak at gmail.com> >>
383 with plenty of code borrowed from L<Class::MOP> and L<Moose>
389 Please report any bugs through RT: email
390 C<bug-mouse at rt.cpan.org>, or browse
391 L<http://rt.cpan.org/NoAuth/ReportBug.html?Queue=Mouse>.
393 =head1 COPYRIGHT AND LICENSE
395 Copyright 2008 Shawn M Moore.
397 This program is free software; you can redistribute it and/or modify it
398 under the same terms as Perl itself.