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 if ($name =~ s/^\+//) {
43 Mouse::Meta::Attribute->clone_parent($package, $name, @_);
46 Mouse::Meta::Attribute->create($package, $name, @_);
61 return \&Class::Method::Modifiers::before;
65 return \&Class::Method::Modifiers::after;
69 return \&Class::Method::Modifiers::around;
73 my $exporter = Sub::Exporter::build_exporter({
75 groups => { default => [':all'] },
84 my $meta = Mouse::Meta::Class->initialize($CALLER);
85 $meta->superclasses('Mouse::Object')
86 unless $meta->superclasses;
95 for my $keyword (keys %exports) {
96 next if $keyword eq 'meta'; # we don't delete this one
97 delete ${ $caller . '::' }{$keyword};
105 if (ref($class) || !defined($class) || !length($class)) {
106 my $display = defined($class) ? $class : 'undef';
107 confess "Invalid class name ($display)";
110 return 1 if is_class_loaded($class);
112 (my $file = "$class.pm") =~ s{::}{/}g;
114 eval { CORE::require($file) };
115 confess "Could not load class ($class) because : $@" if $@;
120 sub is_class_loaded {
123 return 0 if ref($class) || !defined($class) || !length($class);
125 # walk the symbol table tree to avoid autovififying
126 # \*{${main::}{"Foo::"}} == \*main::Foo::
129 foreach my $part (split('::', $class)) {
130 return 0 unless exists ${$$pack}{"${part}::"};
131 $pack = \*{${$$pack}{"${part}::"}};
134 # check for $VERSION or @ISA
135 return 1 if exists ${$$pack}{VERSION}
136 && defined *{${$$pack}{VERSION}}{SCALAR};
137 return 1 if exists ${$$pack}{ISA}
138 && defined *{${$$pack}{ISA}}{ARRAY};
140 # check for any method
141 foreach ( keys %{$$pack} ) {
142 next if substr($_, -2, 2) eq '::';
143 return 1 if defined *{${$$pack}{$_}}{CODE};
156 Mouse - Moose minus the antlers
161 use Mouse; # automatically turns on strict and warnings
163 has 'x' => (is => 'rw', isa => 'Int');
164 has 'y' => (is => 'rw', isa => 'Int');
177 has 'z' => (is => 'rw', isa => 'Int');
179 after 'clear' => sub {
186 L<Moose> is wonderful.
188 Unfortunately, it's a little slow. Though significant progress has been made
189 over the years, the compile time penalty is a non-starter for some
192 Mouse aims to alleviate this by providing a subset of Moose's
193 functionality, faster. In particular, L<Moose/has> is missing only a few
194 expert-level features.
198 Compatibility with Moose has been the utmost concern. Fewer than 1% of the
199 tests fail when run against Moose instead of Mouse. Mouse code coverage is also
200 over 99%. Even the error messages are taken from Moose. The Mouse code just
201 runs the test suite 3x-4x faster.
203 The idea is that, if you need the extra power, you should be able to run
204 C<s/Mouse/Moose/g> on your codebase and have nothing break. To that end,
205 nothingmuch has written L<Squirrel> (part of this distribution) which will act
206 as Mouse unless Moose is loaded, in which case it will act as Moose.
208 Mouse also has the blessings of Moose's author, stevan.
210 =head2 MISSING FEATURES
214 Fixing this one slightly less soon. stevan has suggested an implementation
215 strategy. Mouse currently mostly ignores methods.
219 User-defined type constraints and parameterized types may be implemented. Type
220 coercions probably not (patches welcome).
222 =head3 Bootstrapped meta world
224 Very handy for extensions to the MOP. Not pressing, but would be nice to have.
226 =head3 Modification of attribute metaclass
228 When you declare an attribute with L</has>, you get the inlined accessors
229 installed immediately. Modifying the attribute metaclass, even if possible,
238 =head2 meta -> Mouse::Meta::Class
240 Returns this class' metaclass instance.
242 =head2 extends superclasses
244 Sets this class' superclasses.
246 =head2 before (method|methods) => Code
248 Installs a "before" method modifier. See L<Moose/before> or
249 L<Class::Method::Modifiers/before>.
251 =head2 after (method|methods) => Code
253 Installs an "after" method modifier. See L<Moose/after> or
254 L<Class::Method::Modifiers/after>.
256 =head2 around (method|methods) => Code
258 Installs an "around" method modifier. See L<Moose/around> or
259 L<Class::Method::Modifiers/around>.
261 =head2 has (name|names) => parameters
263 Adds an attribute (or if passed an arrayref of names, multiple attributes) to
270 If specified, inlines a read-only/read-write accessor with the same name as
273 =item isa => TypeConstraint
275 Provides basic type checking in the constructor and accessor. Basic types such
276 as C<Int>, C<ArrayRef>, C<Defined> are supported. Any unknown type is taken to
277 be a class check (e.g. isa => 'DateTime' would accept only L<DateTime>
280 =item required => 0|1
282 Whether this attribute is required to have a value. If the attribute is lazy or
283 has a builder, then providing a value for the attribute in the constructor is
286 =item init_arg => Str
288 Allows you to use a different key name in the constructor.
290 =item default => Value | CodeRef
292 Sets the default value of the attribute. If the default is a coderef, it will
293 be invoked to get the default value. Due to quirks of Perl, any bare reference
294 is forbidden, you must wrap the reference in a coderef. Otherwise, all
295 instances will share the same reference.
299 If specified, the default is calculated on demand instead of in the
302 =item predicate => Str
304 Lets you specify a method name for installing a predicate method, which checks
305 that the attribute has a value. It will not invoke a lazy default or builder
310 Lets you specify a method name for installing a clearer method, which clears
311 the attribute's value from the instance. On the next read, lazy or builder will
314 =item handles => HashRef|ArrayRef
316 Lets you specify methods to delegate to the attribute. ArrayRef forwards the
317 given method names to method calls on the attribute. HashRef maps local method
318 names to remote method names called on the attribute. Other forms of
319 L</handles>, such as regular expression and coderef, are not yet supported.
321 =item weak_ref => 0|1
323 Lets you automatically weaken any reference stored in the attribute.
325 =item trigger => Coderef
327 Any time the attribute's value is set (either through the accessor or the
328 constructor), the trigger is called on it. The trigger receives as arguments
329 the instance, the new value, and the attribute instance.
333 Defines a method name to be called to provide the default value of the
334 attribute. C<< builder => 'build_foo' >> is mostly equivalent to
335 C<< default => sub { $_[0]->build_foo } >>.
337 =item auto_deref => 0|1
339 Allows you to automatically dereference ArrayRef and HashRef attributes in list
340 context. In scalar context, the reference is returned (NOT the list length or
341 bucket status). You must specify an appropriate type constraint to use
346 =head2 confess error -> BOOM
348 L<Carp/confess> for your convenience.
350 =head2 blessed value -> ClassName | undef
352 L<Scalar::Util/blessed> for your convenience.
358 Importing Mouse will default your class' superclass list to L<Mouse::Object>.
359 You may use L</extends> to replace the superclass list.
363 Please unimport Mouse (C<no Mouse>) so that if someone calls one of the
364 keywords (such as L</extends>) it will break loudly instead breaking subtly.
368 =head2 load_class Class::Name
370 This will load a given C<Class::Name> (or die if it's not loadable).
371 This function can be used in place of tricks like
372 C<eval "use $module"> or using C<require>.
374 =head2 is_class_loaded Class::Name -> Bool
376 Returns whether this class is actually loaded or not. It uses a heuristic which
377 involves checking for the existence of C<$VERSION>, C<@ISA>, and any
378 locally-defined method.
382 Shawn M Moore, C<< <sartak at gmail.com> >>
384 with plenty of code borrowed from L<Class::MOP> and L<Moose>
390 Please report any bugs through RT: email
391 C<bug-mouse at rt.cpan.org>, or browse
392 L<http://rt.cpan.org/NoAuth/ReportBug.html?Queue=Mouse>.
394 =head1 COPYRIGHT AND LICENSE
396 Copyright 2008 Shawn M Moore.
398 This program is free software; you can redistribute it and/or modify it
399 under the same terms as Perl itself.