use strict;
use warnings;
-our $VERSION = '0.03';
+our $VERSION = '0.05';
use Scalar::Util 'blessed', 'reftype';
use Carp 'confess';
use Sub::Name 'subname';
use UNIVERSAL::require;
+use Sub::Exporter;
use Class::MOP;
use Moose::Meta::Class;
-use Moose::Meta::Attribute;
use Moose::Meta::TypeConstraint;
use Moose::Meta::TypeCoercion;
+use Moose::Meta::Attribute;
+use Moose::Meta::Instance;
use Moose::Object;
use Moose::Util::TypeConstraints;
-sub import {
- shift;
- my $pkg = caller();
-
- # we should never export to main
- return if $pkg eq 'main';
-
- Moose::Util::TypeConstraints->import($pkg);
-
- # make a subtype for each Moose class
- subtype $pkg
- => as Object
- => where { $_->isa($pkg) };
-
- my $meta;
- if ($pkg->can('meta')) {
- $meta = $pkg->meta();
- (blessed($meta) && $meta->isa('Class::MOP::Class'))
- || confess "Whoops, not møøsey enough";
- }
- else {
- $meta = Moose::Meta::Class->initialize($pkg => (
- ':attribute_metaclass' => 'Moose::Meta::Attribute'
- ));
- $meta->add_method('meta' => sub {
- # re-initialize so it inherits properly
- Moose::Meta::Class->initialize($pkg => (
- ':attribute_metaclass' => 'Moose::Meta::Attribute'
- ));
- })
- }
-
- # NOTE:
- # &alias_method will install the method, but it
- # will not name it with
-
- # handle superclasses
- $meta->alias_method('extends' => subname 'Moose::extends' => sub {
- foreach my $super (@_) {
- # see if this is already
- # loaded in the symbol table
- next if _is_class_already_loaded($super);
- # otherwise require it ...
- ($super->require)
- || confess "Could not load superclass '$super' because : " . $UNIVERSAL::require::ERROR;
- }
- $meta->superclasses(@_)
- });
-
- # handle attributes
- $meta->alias_method('has' => subname 'Moose::has' => sub {
- my ($name, %options) = @_;
- if (exists $options{is}) {
- if ($options{is} eq 'ro') {
- $options{reader} = $name;
- }
- elsif ($options{is} eq 'rw') {
- $options{accessor} = $name;
- }
- }
- if (exists $options{isa}) {
- # allow for anon-subtypes here ...
- if (blessed($options{isa}) && $options{isa}->isa('Moose::Meta::TypeConstraint')) {
- $options{type_constraint} = $options{isa};
- }
- else {
- # otherwise assume it is a constraint
- my $constraint = find_type_constraint($options{isa});
- # if the constraing it not found ....
- unless (defined $constraint) {
- # assume it is a foreign class, and make
- # an anon constraint for it
- $constraint = subtype Object => where { $_->isa($options{isa}) };
- }
- $options{type_constraint} = $constraint;
- }
- }
- $meta->add_attribute($name, %options)
- });
-
- # handle method modifers
- $meta->alias_method('before' => subname 'Moose::before' => sub {
- my $code = pop @_;
- $meta->add_before_method_modifier($_, $code) for @_;
- });
- $meta->alias_method('after' => subname 'Moose::after' => sub {
- my $code = pop @_;
- $meta->add_after_method_modifier($_, $code) for @_;
- });
- $meta->alias_method('around' => subname 'Moose::around' => sub {
- my $code = pop @_;
- $meta->add_around_method_modifier($_, $code) for @_;
- });
-
- # make sure they inherit from Moose::Object
- $meta->superclasses('Moose::Object')
- unless $meta->superclasses();
-
- # we recommend using these things
- # so export them for them
- $meta->alias_method('confess' => \&Carp::confess);
- $meta->alias_method('blessed' => \&Scalar::Util::blessed);
+{
+ my $CALLER;
+
+ sub _init_meta {
+ my $class = $CALLER;
+
+ # make a subtype for each Moose class
+ subtype $class
+ => as 'Object'
+ => where { $_->isa($class) }
+ unless find_type_constraint($class);
+
+ my $meta;
+ if ($class->can('meta')) {
+ # NOTE:
+ # this is the case where the metaclass pragma
+ # was used before the 'use Moose' statement to
+ # override a specific class
+ $meta = $class->meta();
+ (blessed($meta) && $meta->isa('Moose::Meta::Class'))
+ || confess "Whoops, not møøsey enough";
+ }
+ else {
+ # NOTE:
+ # this is broken currently, we actually need
+ # to allow the possiblity of an inherited
+ # meta, which will not be visible until the
+ # user 'extends' first. This needs to have
+ # more intelligence to it
+ $meta = Moose::Meta::Class->initialize($class);
+ $meta->add_method('meta' => sub {
+ # re-initialize so it inherits properly
+ Moose::Meta::Class->initialize(blessed($_[0]) || $_[0]);
+ })
+ }
+
+ # make sure they inherit from Moose::Object
+ $meta->superclasses('Moose::Object')
+ unless $meta->superclasses();
+ }
+
+ my %exports = (
+ extends => sub {
+ my $class = $CALLER;
+ return subname 'Moose::extends' => sub {
+ _load_all_classes(@_);
+ my $meta = $class->meta;
+ foreach my $super (@_) {
+ # don't bother if it does not have a meta.
+ next unless $super->can('meta');
+ # if it's meta is a vanilla Moose,
+ # then we can safely ignore it.
+ next if blessed($super->meta) eq 'Moose::Meta::Class';
+ # but if we have anything else,
+ # we need to check it out ...
+ unless (# see if of our metaclass is incompatible
+ ($meta->isa(blessed($super->meta)) &&
+ # and see if our instance metaclass is incompatible
+ $meta->instance_metaclass->isa($super->meta->instance_metaclass)) &&
+ # ... and if we are just a vanilla Moose
+ $meta->isa('Moose::Meta::Class')) {
+ # re-initialize the meta ...
+ my $super_meta = $super->meta;
+ # NOTE:
+ # We might want to consider actually
+ # transfering any attributes from the
+ # original meta into this one, but in
+ # general you should not have any there
+ # at this point anyway, so it's very
+ # much an obscure edge case anyway
+ $meta = $super_meta->reinitialize($class => (
+ ':attribute_metaclass' => $super_meta->attribute_metaclass,
+ ':method_metaclass' => $super_meta->method_metaclass,
+ ':instance_metaclass' => $super_meta->instance_metaclass,
+ ));
+ }
+ }
+ $meta->superclasses(@_);
+ };
+ },
+ with => sub {
+ my $class = $CALLER;
+ return subname 'Moose::with' => sub {
+ my ($role) = @_;
+ _load_all_classes($role);
+ ($role->can('meta') && $role->meta->isa('Moose::Meta::Role'))
+ || confess "You can only consume roles, $role is not a Moose role";
+ $role->meta->apply($class->meta);
+ };
+ },
+ has => sub {
+ my $class = $CALLER;
+ return subname 'Moose::has' => sub {
+ my ($name, %options) = @_;
+ my $meta = $class->meta;
+ if ($name =~ /^\+(.*)/) {
+ my $inherited_attr = $meta->find_attribute_by_name($1);
+ (defined $inherited_attr)
+ || confess "Could not find an attribute by the name of '$1' to inherit from";
+ my $new_attr = $inherited_attr->clone_and_inherit_options(%options);
+ $meta->add_attribute($new_attr);
+ }
+ else {
+ if ($options{metaclass}) {
+ _load_all_classes($options{metaclass});
+ $meta->add_attribute($options{metaclass}->new($name, %options));
+ }
+ else {
+ $meta->add_attribute($name, %options);
+ }
+ }
+ };
+ },
+ before => sub {
+ my $class = $CALLER;
+ return subname 'Moose::before' => sub {
+ my $code = pop @_;
+ my $meta = $class->meta;
+ $meta->add_before_method_modifier($_, $code) for @_;
+ };
+ },
+ after => sub {
+ my $class = $CALLER;
+ return subname 'Moose::after' => sub {
+ my $code = pop @_;
+ my $meta = $class->meta;
+ $meta->add_after_method_modifier($_, $code) for @_;
+ };
+ },
+ around => sub {
+ my $class = $CALLER;
+ return subname 'Moose::around' => sub {
+ my $code = pop @_;
+ my $meta = $class->meta;
+ $meta->add_around_method_modifier($_, $code) for @_;
+ };
+ },
+ super => sub {
+ return subname 'Moose::super' => sub {};
+ },
+ override => sub {
+ my $class = $CALLER;
+ return subname 'Moose::override' => sub {
+ my ($name, $method) = @_;
+ $class->meta->add_override_method_modifier($name => $method);
+ };
+ },
+ inner => sub {
+ return subname 'Moose::inner' => sub {};
+ },
+ augment => sub {
+ my $class = $CALLER;
+ return subname 'Moose::augment' => sub {
+ my ($name, $method) = @_;
+ $class->meta->add_augment_method_modifier($name => $method);
+ };
+ },
+ confess => sub {
+ return \&Carp::confess;
+ },
+ blessed => sub {
+ return \&Scalar::Util::blessed;
+ },
+ all_methods => sub {
+ subname 'Moose::all_methods' => sub () {
+ sub {
+ my ($class, $delegate_class) = @_;
+ $delegate_class->compute_all_applicable_methods();
+ }
+ }
+ }
+ );
+
+ my $exporter = Sub::Exporter::build_exporter({
+ exports => \%exports,
+ groups => {
+ default => [':all']
+ }
+ });
+
+ sub import {
+ $CALLER = caller();
+
+ # we should never export to main
+ return if $CALLER eq 'main';
+
+ _init_meta();
+
+ goto $exporter;
+ }
+}
+
+## Utility functions
+
+sub _load_all_classes {
+ foreach my $super (@_) {
+ # see if this is already
+ # loaded in the symbol table
+ next if _is_class_already_loaded($super);
+ # otherwise require it ...
+ ($super->require)
+ || confess "Could not load superclass '$super' because : " . $UNIVERSAL::require::ERROR;
+ }
}
sub _is_class_already_loaded {
=head1 CAVEAT
-This is a B<very> early release of this module, it still needs
+This is an early release of this module, it still needs
some fine tuning and B<lots> more documentation. I am adopting
the I<release early and release often> approach with this module,
so keep an eye on your favorite CPAN mirror!
=item Moose Offers Often Super Extensions
+=item Meta Object Orientation Syntax Extensions
+
=back
=head1 BUILDING CLASSES WITH MOOSE
all instance slots, setting defaults where approprtiate and performing any
type constraint checking or coercion.
+For more details, see the ever expanding L<Moose::Cookbook>.
+
=head1 EXPORTED FUNCTIONS
Moose will export a number of functions into the class's namespace, which
replace it. This is important to ensure that classes which do not have
superclasses properly inherit from L<Moose::Object>.
+=item B<with ($role)>
+
+This will apply a given C<$role> to the local class. Role support is
+currently very experimental, see L<Moose::Role> for more details.
+
=item B<has ($name, %options)>
This will install an attribute of a given C<$name> into the current class.
string. The string can be either a class name, or a type defined using
Moose's type defintion features.
+=item I<coerce =E<gt> (1|0)>
+
+This will attempt to use coercion with the supplied type constraint to change
+the value passed into any accessors of constructors. You B<must> have supplied
+a type constraint in order for this to work. See L<Moose::Cookbook::Recipe5>
+for an example usage.
+
+=item I<does =E<gt> $role_name>
+
+This will accept the name of a role which the value stored in this attribute
+is expected to have consumed.
+
+=item I<required =E<gt> (1|0)>
+
+This marks the attribute as being required. This means a value must be supplied
+during class construction, and the attribute can never be set to C<undef> with
+an accessor.
+
+=item I<weak_ref =E<gt> (1|0)>
+
+This will tell the class to strore the value of this attribute as a weakened
+reference. If an attribute is a weakened reference, it can B<not> also be coerced.
+
+=item I<lazy =E<gt> (1|0)>
+
+This will tell the class to not create this slot until absolutely nessecary.
+If an attribute is marked as lazy it B<must> have a default supplied.
+
+=item I<trigger =E<gt> $code>
+
+The trigger option is a CODE reference which will be called after the value of
+the attribute is set. The CODE ref will be passed the instance itself, the
+updated value and the attribute meta-object (this is for more advanced fiddling
+and can typically be ignored in most cases). You can B<not> have a trigger on
+a read-only attribute.
+
=back
=item B<before $name|@names =E<gt> sub { ... }>
modifier features that L<Class::MOP> provides. More information on these can
be found in the L<Class::MOP> documentation for now.
+=item B<super>
+
+The keyword C<super> is a noop when called outside of an C<override> method. In
+the context of an C<override> method, it will call the next most appropriate
+superclass method with the same arguments as the original method.
+
+=item B<override ($name, &sub)>
+
+An C<override> method, is a way of explictly saying "I am overriding this
+method from my superclass". You can call C<super> within this method, and
+it will work as expected. The same thing I<can> be accomplished with a normal
+method call and the C<SUPER::> pseudo-package, it is really your choice.
+
+=item B<inner>
+
+The keyword C<inner>, much like C<super>, is a no-op outside of the context of
+an C<augment> method. You can think of C<inner> as being the inverse of
+C<super>, the details of how C<inner> and C<augment> work is best described in
+the L<Moose::Cookbook>.
+
+=item B<augment ($name, &sub)>
+
+An C<augment> method, is a way of explictly saying "I am augmenting this
+method from my superclass". Once again, the details of how C<inner> and
+C<augment> work is best described in the L<Moose::Cookbook>.
+
=item B<confess>
This is the C<Carp::confess> function, and exported here beause I use it
=back
+=head1 CAVEATS
+
+=over 4
+
+=item *
+
+It should be noted that C<super> and C<inner> can B<not> be used in the same
+method. However, they can be combined together with the same class hierarchy,
+see F<t/014_override_augment_inner_super.t> for an example.
+
+The reason that this is so is because C<super> is only valid within a method
+with the C<override> modifier, and C<inner> will never be valid within an
+C<override> method. In fact, C<augment> will skip over any C<override> methods
+when searching for it's appropriate C<inner>.
+
+This might seem like a restriction, but I am of the opinion that keeping these
+two features seperate (but interoperable) actually makes them easy to use since
+their behavior is then easier to predict. Time will tell if I am right or not.
+
+=back
+
=head1 ACKNOWLEDGEMENTS
=over 4
=item L<http://forum2.org/moose/>
+=item L<http://www.cs.utah.edu/plt/publications/oopsla04-gff.pdf>
+
+This paper (suggested by lbr on #moose) was what lead to the implementation
+of the C<super>/C<overrride> and C<inner>/C<augment> features. If you really
+want to understand this feature, I suggest you read this.
+
=back
=head1 BUGS
This library is free software; you can redistribute it and/or modify
it under the same terms as Perl itself.
-=cut
\ No newline at end of file
+=cut
projects / gitmo/Moose.git / blobdiff