9 use Scalar::Util 'blessed', 'reftype';
11 use Sub::Name 'subname';
13 use UNIVERSAL::require;
17 use Moose::Meta::Class;
18 use Moose::Meta::Attribute;
19 use Moose::Meta::TypeConstraint;
20 use Moose::Meta::TypeCoercion;
23 use Moose::Util::TypeConstraints;
29 # we should never export to main
30 return if $pkg eq 'main';
32 Moose::Util::TypeConstraints->import($pkg);
34 # make a subtype for each Moose class
37 => where { $_->isa($pkg) };
40 if ($pkg->can('meta')) {
42 (blessed($meta) && $meta->isa('Class::MOP::Class'))
43 || confess "Whoops, not møøsey enough";
46 $meta = Moose::Meta::Class->initialize($pkg => (
47 ':attribute_metaclass' => 'Moose::Meta::Attribute'
49 $meta->add_method('meta' => sub {
50 # re-initialize so it inherits properly
51 Moose::Meta::Class->initialize($pkg => (
52 ':attribute_metaclass' => 'Moose::Meta::Attribute'
58 # &alias_method will install the method, but it
59 # will not name it with
62 $meta->alias_method('extends' => subname 'Moose::extends' => sub {
64 $meta->superclasses(@_)
68 $meta->alias_method('has' => subname 'Moose::has' => sub {
69 my ($name, %options) = @_;
70 if (exists $options{is}) {
71 if ($options{is} eq 'ro') {
72 $options{reader} = $name;
74 elsif ($options{is} eq 'rw') {
75 $options{accessor} = $name;
78 if (exists $options{isa}) {
79 # allow for anon-subtypes here ...
80 if (blessed($options{isa}) && $options{isa}->isa('Moose::Meta::TypeConstraint')) {
81 $options{type_constraint} = $options{isa};
84 # otherwise assume it is a constraint
85 my $constraint = find_type_constraint($options{isa});
86 # if the constraing it not found ....
87 unless (defined $constraint) {
88 # assume it is a foreign class, and make
89 # an anon constraint for it
90 $constraint = subtype Object => where { $_->isa($options{isa}) };
92 $options{type_constraint} = $constraint;
95 $meta->add_attribute($name, %options)
98 # handle method modifers
99 $meta->alias_method('before' => subname 'Moose::before' => sub {
101 $meta->add_before_method_modifier($_, $code) for @_;
103 $meta->alias_method('after' => subname 'Moose::after' => sub {
105 $meta->add_after_method_modifier($_, $code) for @_;
107 $meta->alias_method('around' => subname 'Moose::around' => sub {
109 $meta->add_around_method_modifier($_, $code) for @_;
112 # make sure they inherit from Moose::Object
113 $meta->superclasses('Moose::Object')
114 unless $meta->superclasses();
116 # we recommend using these things
117 # so export them for them
118 $meta->alias_method('confess' => \&Carp::confess);
119 $meta->alias_method('blessed' => \&Scalar::Util::blessed);
130 Moose - Moose, it's the new Camel
137 has 'x' => (isa => 'Int', is => 'rw');
138 has 'y' => (isa => 'Int', is => 'rw');
151 has 'z' => (isa => 'Int');
153 after 'clear' => sub {
160 This is a B<very> early release of this module, it still needs
161 some fine tuning and B<lots> more documentation. I am adopting
162 the I<release early and release often> approach with this module,
163 so keep an eye on your favorite CPAN mirror!
167 Moose is an extension of the Perl 5 object system.
169 =head2 Another object system!?!?
171 Yes, I know there has been an explosion recently of new ways to
172 build object's in Perl 5, most of them based on inside-out objects,
173 and other such things. Moose is different because it is not a new
174 object system for Perl 5, but instead an extension of the existing
177 Moose is built on top of L<Class::MOP>, which is a metaclass system
178 for Perl 5. This means that Moose not only makes building normal
179 Perl 5 objects better, but it also provides the power of metaclass
182 =head2 What does Moose stand for??
184 Moose doesn't stand for one thing in particular, however, if you
185 want, here are a few of my favorites, feel free to contribute
190 =item Make Other Object Systems Envious
192 =item Makes Object Orientation So Easy
194 =item Makes Object Orientation Spiffy- Er (sorry ingy)
196 =item Most Other Object Systems Emasculate
198 =item My Overcraft Overfilled (with) Some Eels
200 =item Moose Often Ovulate Sorta Early
202 =item Many Overloaded Object Systems Exists
204 =item Moose Offers Often Super Extensions
208 =head1 BUILDING CLASSES WITH MOOSE
210 Moose makes every attempt to provide as much convience during class
211 construction/definition, but still stay out of your way if you want
212 it to. Here are some of the features Moose provides:
214 Unless specified with C<extends>, any class which uses Moose will
215 inherit from L<Moose::Object>.
217 Moose will also manage all attributes (including inherited ones) that
218 are defined with C<has>. And assuming that you call C<new> which is
219 inherited from L<Moose::Object>, then this includes properly initializing
220 all instance slots, setting defaults where approprtiate and performing any
221 type constraint checking or coercion.
223 =head1 EXPORTED FUNCTIONS
225 Moose will export a number of functions into the class's namespace, which
226 can then be used to set up the class. These functions all work directly
227 on the current class.
233 This is a method which provides access to the current class's metaclass.
235 =item B<extends (@superclasses)>
237 This function will set the superclass(es) for the current class.
239 This approach is recommended instead of C<use base>, because C<use base>
240 actually C<push>es onto the class's C<@ISA>, whereas C<extends> will
241 replace it. This is important to ensure that classes which do not have
242 superclasses properly inherit from L<Moose::Object>.
244 =item B<has ($name, %options)>
246 This will install an attribute of a given C<$name> into the current class.
247 The list of C<%options> are the same as those provided by both
248 L<Class::MOP::Attribute> and L<Moose::Meta::Attribute>, in addition to a
249 few convience ones provided by Moose which are listed below:
253 =item I<is =E<gt> 'rw'|'ro'>
255 The I<is> option accepts either I<rw> (for read/write) or I<ro> (for read
256 only). These will create either a read/write accessor or a read-only
257 accessor respectively, using the same name as the C<$name> of the attribute.
259 If you need more control over how your accessors are named, you can use the
260 I<reader>, I<writer> and I<accessor> options inherited from L<Moose::Meta::Attribute>.
262 =item I<isa =E<gt> $type_name>
264 The I<isa> option uses Moose's type constraint facilities to set up runtime
265 type checking for this attribute. Moose will perform the checks during class
266 construction, and within any accessors. The C<$type_name> argument must be a
267 string. The string can be either a class name, or a type defined using
268 Moose's type defintion features.
272 =item B<before $name|@names =E<gt> sub { ... }>
274 =item B<after $name|@names =E<gt> sub { ... }>
276 =item B<around $name|@names =E<gt> sub { ... }>
278 This three items are syntactic sugar for the before, after and around method
279 modifier features that L<Class::MOP> provides. More information on these can
280 be found in the L<Class::MOP> documentation for now.
284 This is the C<Carp::confess> function, and exported here beause I use it
285 all the time. This feature may change in the future, so you have been warned.
289 This is the C<Scalar::Uti::blessed> function, it is exported here beause I
290 use it all the time. It is highly recommended that this is used instead of
291 C<ref> anywhere you need to test for an object's class name.
295 =head1 ACKNOWLEDGEMENTS
299 =item I blame Sam Vilain for introducing me to the insanity that is meta-models.
301 =item I blame Audrey Tang for then encouraging my meta-model habit in #perl6.
303 =item Without Yuval "nothingmuch" Kogman this module would not be possible,
304 and it certainly wouldn't have this name ;P
306 =item The basis of the TypeContraints module was Rob Kinyon's idea
307 originally, I just ran with it.
309 =item Thanks to mst & chansen and the whole #moose poose for all the
310 ideas/feature-requests/encouragement
318 =item L<Class::MOP> documentation
320 =item The #moose channel on irc.perl.org
322 =item L<http://forum2.org/moose/>
328 All complex software has bugs lurking in it, and this module is no
329 exception. If you find a bug please either email me, or add the bug
334 Stevan Little E<lt>stevan@iinteractive.comE<gt>
336 =head1 COPYRIGHT AND LICENSE
338 Copyright 2006 by Infinity Interactive, Inc.
340 L<http://www.iinteractive.com>
342 This library is free software; you can redistribute it and/or modify
343 it under the same terms as Perl itself.