use strict;
use warnings;
+use Class::MOP::Method::Accessor;
+
use Carp 'confess';
use Scalar::Util 'blessed', 'reftype', 'weaken';
-our $VERSION = '0.12';
+our $VERSION = '0.14';
our $AUTHORITY = 'cpan:STEVAN';
+use base 'Class::MOP::Object';
+
sub meta {
require Class::MOP::Class;
Class::MOP::Class->initialize(blessed($_[0]) || $_[0]);
(defined $name && $name)
|| confess "You must provide a name for the attribute";
+
$options{init_arg} = $name
if not exists $options{init_arg};
if exists $options{default} && ref $options{default};
bless {
- name => $name,
- accessor => $options{accessor},
- reader => $options{reader},
- writer => $options{writer},
- predicate => $options{predicate},
- clearer => $options{clearer},
- init_arg => $options{init_arg},
- default => $options{default},
+ '$!name' => $name,
+ '$!accessor' => $options{accessor},
+ '$!reader' => $options{reader},
+ '$!writer' => $options{writer},
+ '$!predicate' => $options{predicate},
+ '$!clearer' => $options{clearer},
+ '$!init_arg' => $options{init_arg},
+ '$!default' => $options{default},
# keep a weakened link to the
# class we are associated with
- associated_class => undef,
+ '$!associated_class' => undef,
+ # and a list of the methods
+ # associated with this attr
+ '@!associated_methods' => [],
} => $class;
}
sub initialize_instance_slot {
my ($self, $meta_instance, $instance, $params) = @_;
- my $init_arg = $self->{init_arg};
+ my $init_arg = $self->{'$!init_arg'};
# try to fetch the init arg from the %params ...
my $val;
$val = $params->{$init_arg} if exists $params->{$init_arg};
# if nothing was in the %params, we can use the
# attribute's default value (if it has one)
- if (!defined $val && defined $self->{default}) {
+ if (!defined $val && defined $self->{'$!default'}) {
$val = $self->default($instance);
}
$meta_instance->set_slot_value($instance, $self->name, $val);
# the next bunch of methods will get bootstrapped
# away in the Class::MOP bootstrapping section
-sub name { $_[0]->{name} }
+sub name { $_[0]->{'$!name'} }
-sub associated_class { $_[0]->{associated_class} }
+sub associated_class { $_[0]->{'$!associated_class'} }
+sub associated_methods { $_[0]->{'@!associated_methods'} }
-sub has_accessor { defined($_[0]->{accessor}) ? 1 : 0 }
-sub has_reader { defined($_[0]->{reader}) ? 1 : 0 }
-sub has_writer { defined($_[0]->{writer}) ? 1 : 0 }
-sub has_predicate { defined($_[0]->{predicate}) ? 1 : 0 }
-sub has_clearer { defined($_[0]->{clearer}) ? 1 : 0 }
-sub has_init_arg { defined($_[0]->{init_arg}) ? 1 : 0 }
-sub has_default { defined($_[0]->{default}) ? 1 : 0 }
+sub has_accessor { defined($_[0]->{'$!accessor'}) ? 1 : 0 }
+sub has_reader { defined($_[0]->{'$!reader'}) ? 1 : 0 }
+sub has_writer { defined($_[0]->{'$!writer'}) ? 1 : 0 }
+sub has_predicate { defined($_[0]->{'$!predicate'}) ? 1 : 0 }
+sub has_clearer { defined($_[0]->{'$!clearer'}) ? 1 : 0 }
+sub has_init_arg { defined($_[0]->{'$!init_arg'}) ? 1 : 0 }
+sub has_default { defined($_[0]->{'$!default'}) ? 1 : 0 }
-sub accessor { $_[0]->{accessor} }
-sub reader { $_[0]->{reader} }
-sub writer { $_[0]->{writer} }
-sub predicate { $_[0]->{predicate} }
-sub clearer { $_[0]->{clearer} }
-sub init_arg { $_[0]->{init_arg} }
+sub accessor { $_[0]->{'$!accessor'} }
+sub reader { $_[0]->{'$!reader'} }
+sub writer { $_[0]->{'$!writer'} }
+sub predicate { $_[0]->{'$!predicate'} }
+sub clearer { $_[0]->{'$!clearer'} }
+sub init_arg { $_[0]->{'$!init_arg'} }
# end bootstrapped away method section.
# (all methods below here are kept intact)
+sub get_read_method { $_[0]->reader || $_[0]->accessor }
+sub get_write_method { $_[0]->writer || $_[0]->accessor }
+
sub is_default_a_coderef {
- ('CODE' eq (reftype($_[0]->{default}) || ''))
+ ('CODE' eq (reftype($_[0]->{'$!default'} || $_[0]->{default}) || ''))
}
sub default {
my ($self, $instance) = @_;
- if ($instance && $self->is_default_a_coderef) {
+ if (defined $instance && $self->is_default_a_coderef) {
# if the default is a CODE ref, then
# we pass in the instance and default
# can return a value based on that
# instance. Somewhat crude, but works.
- return $self->{default}->($instance);
+ return $self->{'$!default'}->($instance);
}
- $self->{default};
+ $self->{'$!default'};
}
# slots
my ($self, $class) = @_;
(blessed($class) && $class->isa('Class::MOP::Class'))
|| confess "You must pass a Class::MOP::Class instance (or a subclass)";
- weaken($self->{associated_class} = $class);
+ weaken($self->{'$!associated_class'} = $class);
}
sub detach_from_class {
my $self = shift;
- $self->{associated_class} = undef;
+ $self->{'$!associated_class'} = undef;
+}
+
+# method association
+
+sub associate_method {
+ my ($self, $method) = @_;
+ push @{$self->{'@!associated_methods'}} => $method;
}
## Slot management
sub set_value {
my ($self, $instance, $value) = @_;
- Class::MOP::Class->initialize(Scalar::Util::blessed($instance))
+ Class::MOP::Class->initialize(blessed($instance))
->get_meta_instance
- ->set_slot_value( $instance, $self->name, $value );
+ ->set_slot_value($instance, $self->name, $value);
}
sub get_value {
my ($self, $instance) = @_;
- Class::MOP::Class->initialize(Scalar::Util::blessed($instance))
+ Class::MOP::Class->initialize(blessed($instance))
->get_meta_instance
->get_slot_value($instance, $self->name);
}
-## Method generation helpers
-
-sub generate_accessor_method {
- my $attr = shift;
- return sub {
- $attr->set_value($_[0], $_[1]) if scalar(@_) == 2;
- $attr->get_value($_[0]);
- };
-}
-
-sub generate_accessor_method_inline {
- my $self = shift;
- my $attr_name = $self->name;
- my $meta_instance = $self->associated_class->instance_metaclass;
-
- my $code = eval 'sub {'
- . $meta_instance->inline_set_slot_value('$_[0]', "'$attr_name'", '$_[1]') . ' if scalar(@_) == 2; '
- . $meta_instance->inline_get_slot_value('$_[0]', "'$attr_name'")
- . '}';
- confess "Could not generate inline accessor because : $@" if $@;
-
- return $code;
-}
-
-sub generate_reader_method {
- my $attr = shift;
- return sub {
- confess "Cannot assign a value to a read-only accessor" if @_ > 1;
- $attr->get_value($_[0]);
- };
-}
-
-sub generate_reader_method_inline {
- my $self = shift;
- my $attr_name = $self->name;
- my $meta_instance = $self->associated_class->instance_metaclass;
-
- my $code = eval 'sub {'
- . 'confess "Cannot assign a value to a read-only accessor" if @_ > 1;'
- . $meta_instance->inline_get_slot_value('$_[0]', "'$attr_name'")
- . '}';
- confess "Could not generate inline accessor because : $@" if $@;
-
- return $code;
-}
-
-sub generate_writer_method {
- my $attr = shift;
- return sub {
- $attr->set_value($_[0], $_[1]);
- };
-}
-
-sub generate_writer_method_inline {
- my $self = shift;
- my $attr_name = $self->name;
- my $meta_instance = $self->associated_class->instance_metaclass;
-
- my $code = eval 'sub {'
- . $meta_instance->inline_set_slot_value('$_[0]', "'$attr_name'", '$_[1]')
- . '}';
- confess "Could not generate inline accessor because : $@" if $@;
-
- return $code;
-}
-
-sub generate_predicate_method {
- my $self = shift;
- my $attr_name = $self->name;
- return sub {
- defined Class::MOP::Class->initialize(Scalar::Util::blessed($_[0]))
- ->get_meta_instance
- ->get_slot_value($_[0], $attr_name) ? 1 : 0;
- };
-}
-
-sub generate_clearer_method {
- my $self = shift;
- my $attr_name = $self->name;
- return sub {
- Class::MOP::Class->initialize(Scalar::Util::blessed($_[0]))
- ->get_meta_instance
- ->deinitialize_slot($_[0], $attr_name);
- };
+sub has_value {
+ my ($self, $instance) = @_;
+
+ defined Class::MOP::Class->initialize(blessed($instance))
+ ->get_meta_instance
+ ->get_slot_value($instance, $self->name) ? 1 : 0;
}
-sub generate_predicate_method_inline {
- my $self = shift;
- my $attr_name = $self->name;
- my $meta_instance = $self->associated_class->instance_metaclass;
-
- my $code = eval 'sub {'
- . 'defined ' . $meta_instance->inline_get_slot_value('$_[0]', "'$attr_name'") . ' ? 1 : 0'
- . '}';
- confess "Could not generate inline predicate because : $@" if $@;
-
- return $code;
+sub clear_value {
+ my ($self, $instance) = @_;
+
+ Class::MOP::Class->initialize(blessed($instance))
+ ->get_meta_instance
+ ->deinitialize_slot($instance, $self->name);
}
-sub generate_clearer_method_inline {
- my $self = shift;
- my $attr_name = $self->name;
- my $meta_instance = $self->associated_class->instance_metaclass;
-
- my $code = eval 'sub {'
- . $meta_instance->inline_deinitialize_slot('$_[0]', "'$attr_name'")
- . '}';
- confess "Could not generate inline clearer because : $@" if $@;
+## load em up ...
- return $code;
-}
+sub accessor_metaclass { 'Class::MOP::Method::Accessor' }
sub process_accessors {
my ($self, $type, $accessor, $generate_as_inline_methods) = @_;
(reftype($accessor) eq 'HASH')
|| confess "bad accessor/reader/writer/predicate/clearer format, must be a HASH ref";
my ($name, $method) = %{$accessor};
- return ($name, Class::MOP::Attribute::Accessor->wrap($method));
+ $method = $self->accessor_metaclass->wrap($method);
+ $self->associate_method($method);
+ return ($name, $method);
}
else {
- my $inline_me = ($generate_as_inline_methods && $self->associated_class->instance_metaclass->is_inlinable);
- my $generator = $self->can('generate_' . $type . '_method' . ($inline_me ? '_inline' : ''));
- ($generator)
- || confess "There is no method generator for the type='$type'";
- if (my $method = $self->$generator($self->name)) {
- return ($accessor => Class::MOP::Attribute::Accessor->wrap($method));
- }
- confess "Could not create the '$type' method for " . $self->name . " because : $@";
+ my $inline_me = ($generate_as_inline_methods && $self->associated_class->instance_metaclass->is_inlinable);
+ my $method;
+ eval {
+ $method = $self->accessor_metaclass->new(
+ attribute => $self,
+ is_inline => $inline_me,
+ accessor_type => $type,
+ );
+ };
+ confess "Could not create the '$type' method for " . $self->name . " because : $@" if $@;
+ $self->associate_method($method);
+ return ($accessor, $method);
}
}
}
my $method = $class->get_method($accessor);
$class->remove_method($accessor)
- if (blessed($method) && $method->isa('Class::MOP::Attribute::Accessor'));
+ if (blessed($method) && $method->isa('Class::MOP::Method::Accessor'));
};
sub remove_accessors {
my $self = shift;
+ # TODO:
+ # we really need to make sure to remove from the
+ # associates methods here as well. But this is
+ # such a slimly used method, I am not worried
+ # about it right now.
$_remove_accessor->($self->accessor(), $self->associated_class()) if $self->has_accessor();
$_remove_accessor->($self->reader(), $self->associated_class()) if $self->has_reader();
$_remove_accessor->($self->writer(), $self->associated_class()) if $self->has_writer();
}
-package Class::MOP::Attribute::Accessor;
-
-use strict;
-use warnings;
-
-use Class::MOP::Method;
-
-our $VERSION = '0.01';
-
-our @ISA = ('Class::MOP::Method');
-
1;
__END__
=head2 Value management
+These methods are basically "backdoors" to the instance, which can be used
+to bypass the regular accessors, but still stay within the context of the MOP.
+
+These methods are not for general use, and should only be used if you really
+know what you are doing.
+
=over 4
-=item set_value $instance, $value
+=item B<set_value ($instance, $value)>
Set the value without going through the accessor. Note that this may be done to
even attributes with just read only accessors.
-=item get_value $instance
+=item B<get_value ($instance)>
Return the value without going through the accessor. Note that this may be done
even to attributes with just write only accessors.
+=item B<has_value ($instance)>
+
+Returns a boolean indicating if the item in the C<$instance> has a value in it.
+This is basically what the default C<predicate> method calls.
+
+=item B<clear_value ($instance)>
+
+This will clear the value in the C<$instance>. This is basically what the default
+C<clearer> would call. Note that this may be done even if the attirbute does not
+have any associated read, write or clear methods.
+
=back
=head2 Informational
Returns a list of slots required by the attribute. This is usually
just one, which is the name of the attribute.
+=item B<get_read_method>
+
+=item B<get_write_method>
+
+Return the name of a method suitable for reading / writing the value of the
+attribute in the associated class. Suitable for use whether C<reader> and
+C<writer> or C<accessor> was used.
+
=back
=head2 Informational predicates
=head2 Class association
+These methods allow you to manage the attributes association with
+the class that contains it. These methods should not be used
+lightly, nor are they very magical, they are mostly used internally
+and by metaclass instances.
+
=over 4
=item B<associated_class>
-=item B<attach_to_class ($class)>
+This returns the metaclass this attribute is associated with.
-=item B<detach_from_class>
+=item B<attach_to_class ($class)>
-=item B<slot_name>
+This will store a weaken reference to C<$class> internally. You should
+note that just changing the class assocation will not remove the attribute
+from it's old class, and initialize it (and it's accessors) in the new
+C<$class>. It is up to you to do this manually.
-=item B<allocate_slots>
+=item B<detach_from_class>
-=item B<deallocate_slots>
+This will remove the weakened reference to the class. It does B<not>
+remove the attribute itself from the class (or remove it's accessors),
+you must do that yourself if you want too. Actually if that is what
+you want to do, you should probably be looking at
+L<Class::MOP::Class::remove_attribute> instead.
=back
=over 4
+=item B<accessor_metaclass>
+
+Accessors are generated by an accessor metaclass, which is usually
+a subclass of C<Class::MOP::Method::Accessor>. This method returns
+the name of the accessor metaclass that this attribute uses.
+
+=item B<associate_method ($method)>
+
+This will associate a C<$method> with the given attribute which is
+used internally by the accessor generator.
+
+=item B<associated_methods>
+
+This will return the list of methods which have been associated with
+the C<associate_method> methods.
+
=item B<install_accessors>
This allows the attribute to generate and install code for it's own
(using the C<generate_*_method> methods listed below) or it will
use the custom method passed through the constructor.
-=over 4
-
-=item B<generate_accessor_method>
-
-=item B<generate_predicate_method>
-
-=item B<generate_clearer_method>
-
-=item B<generate_reader_method>
-
-=item B<generate_writer_method>
-
-=back
-
-=over 4
-
-=item B<generate_accessor_method_inline>
-
-=item B<generate_predicate_method_inline>
-
-=item B<generate_clearer_method_inline>
-
-=item B<generate_reader_method_inline>
-
-=item B<generate_writer_method_inline>
-
-=back
-
=item B<remove_accessors>
This allows the attribute to remove the method for it's own
I<accessor/reader/writer/predicate/clearer>. This is called by
C<Class::MOP::Class::remove_attribute>.
+NOTE: This does not currently remove methods from the list returned
+by C<associated_methods>, that is on the TODO list.
+
=back
=head2 Introspection
=head1 COPYRIGHT AND LICENSE
-Copyright 2006 by Infinity Interactive, Inc.
+Copyright 2006, 2007 by Infinity Interactive, Inc.
L<http://www.iinteractive.com>
projects / gitmo/Class-MOP.git / blobdiff