use Class::MOP::Method::Accessor;
use Carp 'confess';
-use Scalar::Util 'blessed', 'reftype', 'weaken';
+use Scalar::Util 'blessed', 'weaken';
-our $VERSION = '0.12';
+our $VERSION = '0.62';
our $AUTHORITY = 'cpan:STEVAN';
use base 'Class::MOP::Object';
-sub meta {
- require Class::MOP::Class;
- Class::MOP::Class->initialize(blessed($_[0]) || $_[0]);
-}
-
# NOTE: (meta-circularity)
-# This method will be replaced in the
-# boostrap section of Class::MOP, by
-# a new version which uses the
+# This method will be replaced in the
+# boostrap section of Class::MOP, by
+# a new version which uses the
# &Class::MOP::Class::construct_instance
# method to build an attribute meta-object
# which itself is described with attribute
-# meta-objects.
+# meta-objects.
# - Ain't meta-circularity grand? :)
sub new {
my $class = shift;
my $name = shift;
- my %options = @_;
-
+ my %options = @_;
+
(defined $name && $name)
|| confess "You must provide a name for the attribute";
-
- $options{init_arg} = $name
+
+ $options{init_arg} = $name
if not exists $options{init_arg};
-
- (is_default_a_coderef(\%options))
- || confess("References are not allowed as default values, you must ".
- "wrap then in a CODE reference (ex: sub { [] } and not [])")
- if exists $options{default} && ref $options{default};
-
+ if(exists $options{builder}){
+ confess("builder must be a defined scalar value which is a method name")
+ if ref $options{builder} || !(defined $options{builder});
+ confess("Setting both default and builder is not allowed.")
+ if exists $options{default};
+ } else {
+ (is_default_a_coderef(\%options))
+ || confess("References are not allowed as default values, you must ".
+ "wrap the default of '$name' in a CODE reference (ex: sub { [] } and not [])")
+ if exists $options{default} && ref $options{default};
+ }
+ if( $options{required} and not( defined($options{builder}) || defined($options{init_arg}) || exists $options{default} ) ) {
+ confess("A required attribute must have either 'init_arg', 'builder', or '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 => $options{default},
- # keep a weakened link to the
+ '$!name' => $name,
+ '$!accessor' => $options{accessor},
+ '$!reader' => $options{reader},
+ '$!writer' => $options{writer},
+ '$!predicate' => $options{predicate},
+ '$!clearer' => $options{clearer},
+ '$!builder' => $options{builder},
+ '$!init_arg' => $options{init_arg},
+ '$!default' => $options{default},
+ '$!initializer' => $options{initializer},
+ # keep a weakened link to the
# class we are associated with
- associated_class => undef,
- # and a list of the methods
+ '$!associated_class' => undef,
+ # and a list of the methods
# associated with this attr
- associated_methods => [],
+ '@!associated_methods' => [],
+ # NOTE:
+ # protect this from silliness
+ init_arg => undef,
} => $class;
}
# NOTE:
-# this is a primative (and kludgy) clone operation
+# this is a primative (and kludgy) clone operation
# for now, it will be replaced in the Class::MOP
-# bootstrap with a proper one, however we know
+# bootstrap with a proper one, however we know
# that this one will work fine for now.
sub clone {
my $self = shift;
sub initialize_instance_slot {
my ($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
+
+ # if nothing was in the %params, we can use the
# attribute's default value (if it has one)
- if (!defined $val && defined $self->{default}) {
- $val = $self->default($instance);
+ if(defined $init_arg and exists $params->{$init_arg}){
+ $self->_set_initial_slot_value(
+ $meta_instance,
+ $instance,
+ $params->{$init_arg},
+ );
+ }
+ elsif (defined $self->{'$!default'}) {
+ $self->_set_initial_slot_value(
+ $meta_instance,
+ $instance,
+ $self->default($instance),
+ );
+ }
+ elsif (defined( my $builder = $self->{'$!builder'})) {
+ if ($builder = $instance->can($builder)) {
+ $self->_set_initial_slot_value(
+ $meta_instance,
+ $instance,
+ $instance->$builder,
+ );
+ }
+ else {
+ confess(blessed($instance)." does not support builder method '". $self->{'$!builder'} ."' for attribute '" . $self->name . "'");
+ }
}
- $meta_instance->set_slot_value($instance, $self->name, $val);
}
-# NOTE:
-# the next bunch of methods will get bootstrapped
-# away in the Class::MOP bootstrapping section
+sub _set_initial_slot_value {
+ my ($self, $meta_instance, $instance, $value) = @_;
-sub name { $_[0]->{name} }
+ my $slot_name = $self->name;
+
+ return $meta_instance->set_slot_value($instance, $slot_name, $value)
+ unless $self->has_initializer;
+
+ my $callback = sub {
+ $meta_instance->set_slot_value($instance, $slot_name, $_[0]);
+ };
+
+ my $initializer = $self->initializer;
-sub associated_class { $_[0]->{associated_class} }
-sub associated_methods { $_[0]->{associated_methods} }
+ # most things will just want to set a value, so make it first arg
+ $instance->$initializer($value, $callback, $self);
+}
-sub has_accessor { defined($_[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 }
+# NOTE:
+# the next bunch of methods will get bootstrapped
+# away in the Class::MOP bootstrapping section
-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 name { $_[0]->{'$!name'} }
+
+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]->{'$!clearer'}) ? 1 : 0 }
+sub has_builder { defined($_[0]->{'$!builder'}) ? 1 : 0 }
+sub has_init_arg { defined($_[0]->{'$!init_arg'}) ? 1 : 0 }
+sub has_default { defined($_[0]->{'$!default'}) ? 1 : 0 }
+sub has_initializer { defined($_[0]->{'$!initializer'}) ? 1 : 0 }
+
+sub accessor { $_[0]->{'$!accessor'} }
+sub reader { $_[0]->{'$!reader'} }
+sub writer { $_[0]->{'$!writer'} }
+sub predicate { $_[0]->{'$!predicate'} }
+sub clearer { $_[0]->{'$!clearer'} }
+sub builder { $_[0]->{'$!builder'} }
+sub init_arg { $_[0]->{'$!init_arg'} }
+sub initializer { $_[0]->{'$!initializer'} }
# end bootstrapped away method section.
# (all methods below here are kept intact)
-sub is_default_a_coderef {
- ('CODE' eq (reftype($_[0]->{default}) || ''))
+sub has_read_method { $_[0]->has_reader || $_[0]->has_accessor }
+sub has_write_method { $_[0]->has_writer || $_[0]->has_accessor }
+
+sub get_read_method {
+ my $self = shift;
+ my $reader = $self->reader || $self->accessor;
+ # normal case ...
+ return $reader unless ref $reader;
+ # the HASH ref case
+ my ($name) = %$reader;
+ return $name;
+}
+
+sub get_write_method {
+ my $self = shift;
+ my $writer = $self->writer || $self->accessor;
+ # normal case ...
+ return $writer unless ref $writer;
+ # the HASH ref case
+ my ($name) = %$writer;
+ return $name;
+}
+
+sub get_read_method_ref {
+ my $self = shift;
+ if ((my $reader = $self->get_read_method) && $self->associated_class) {
+ return $self->associated_class->get_method($reader);
+ }
+ else {
+ my $code = sub { $self->get_value(@_) };
+ if (my $class = $self->associated_class) {
+ return $class->method_metaclass->wrap(
+ $code,
+ package_name => $class->name,
+ name => '__ANON__'
+ );
+ }
+ else {
+ return $code;
+ }
+ }
+}
+
+sub get_write_method_ref {
+ my $self = shift;
+ if ((my $writer = $self->get_write_method) && $self->associated_class) {
+ return $self->associated_class->get_method($writer);
+ }
+ else {
+ my $code = sub { $self->set_value(@_) };
+ if (my $class = $self->associated_class) {
+ return $class->method_metaclass->wrap(
+ $code,
+ package_name => $class->name,
+ name => '__ANON__'
+ );
+ }
+ else {
+ return $code;
+ }
+ }
+}
+
+sub is_default_a_coderef {
+ ('CODE' eq ref($_[0]->{'$!default'} || $_[0]->{default}))
}
-sub default {
+sub default {
my ($self, $instance) = @_;
- if ($instance && $self->is_default_a_coderef) {
- # if the default is a CODE ref, then
+ 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
+ # can return a value based on that
# instance. Somewhat crude, but works.
- return $self->{default}->($instance);
- }
- $self->{default};
+ return $self->{'$!default'}->($instance);
+ }
+ $self->{'$!default'};
}
# slots
sub slots { (shift)->name }
-# class association
+# class association
sub attach_to_class {
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
+# method association
sub associate_method {
my ($self, $method) = @_;
- push @{$self->{associated_methods}} => $method;
+ push @{$self->{'@!associated_methods'}} => $method;
}
## Slot management
+sub set_initial_value {
+ my ($self, $instance, $value) = @_;
+ $self->_set_initial_slot_value(
+ Class::MOP::Class->initialize(blessed($instance))->get_meta_instance,
+ $instance,
+ $value
+ );
+}
+
sub set_value {
my ($self, $instance, $value) = @_;
sub has_value {
my ($self, $instance) = @_;
-
- defined Class::MOP::Class->initialize(blessed($instance))
- ->get_meta_instance
- ->get_slot_value($instance, $self->name) ? 1 : 0;
+
+ Class::MOP::Class->initialize(blessed($instance))
+ ->get_meta_instance
+ ->is_slot_initialized($instance, $self->name);
}
sub clear_value {
my ($self, $instance) = @_;
-
+
Class::MOP::Class->initialize(blessed($instance))
->get_meta_instance
- ->deinitialize_slot($instance, $self->name);
+ ->deinitialize_slot($instance, $self->name);
}
## load em up ...
sub process_accessors {
my ($self, $type, $accessor, $generate_as_inline_methods) = @_;
- if (reftype($accessor)) {
- (reftype($accessor) eq 'HASH')
+ if (ref($accessor)) {
+ (ref($accessor) eq 'HASH')
|| confess "bad accessor/reader/writer/predicate/clearer format, must be a HASH ref";
my ($name, $method) = %{$accessor};
- $method = $self->accessor_metaclass->wrap($method);
+ $method = $self->accessor_metaclass->wrap(
+ $method,
+ package_name => $self->associated_class->name,
+ name => $name,
+ );
$self->associate_method($method);
- return ($name, $method);
+ return ($name, $method);
}
else {
- my $inline_me = ($generate_as_inline_methods && $self->associated_class->instance_metaclass->is_inlinable);
+ 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,
- );
+ package_name => $self->associated_class->name,
+ name => $accessor,
+ );
};
- confess "Could not create the '$type' method for " . $self->name . " because : $@" if $@;
+ confess "Could not create the '$type' method for " . $self->name . " because : $@" if $@;
$self->associate_method($method);
return ($accessor, $method);
- }
+ }
}
sub install_accessors {
my $self = shift;
my $inline = shift;
my $class = $self->associated_class;
-
+
$class->add_method(
$self->process_accessors('accessor' => $self->accessor(), $inline)
) if $self->has_accessor();
- $class->add_method(
+ $class->add_method(
$self->process_accessors('reader' => $self->reader(), $inline)
) if $self->has_reader();
$class->add_method(
$self->process_accessors('predicate' => $self->predicate(), $inline)
) if $self->has_predicate();
-
+
$class->add_method(
$self->process_accessors('clearer' => $self->clearer(), $inline)
) if $self->has_clearer();
-
+
return;
}
{
my $_remove_accessor = sub {
my ($accessor, $class) = @_;
- if (reftype($accessor) && reftype($accessor) eq 'HASH') {
+ if (ref($accessor) && ref($accessor) eq 'HASH') {
($accessor) = keys %{$accessor};
- }
- my $method = $class->get_method($accessor);
- $class->remove_method($accessor)
+ }
+ my $method = $class->get_method($accessor);
+ $class->remove_method($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();
$_remove_accessor->($self->predicate(), $self->associated_class()) if $self->has_predicate();
$_remove_accessor->($self->clearer(), $self->associated_class()) if $self->has_clearer();
- return;
+ return;
}
}
=pod
-=head1 NAME
+=head1 NAME
Class::MOP::Attribute - Attribute Meta Object
=head1 SYNOPSIS
-
+
Class::MOP::Attribute->new('$foo' => (
accessor => 'foo', # dual purpose get/set accessor
- predicate => 'has_foo' # predicate check for defined-ness
+ predicate => 'has_foo' # predicate check for defined-ness
init_arg => '-foo', # class->new will look for a -foo key
default => 'BAR IS BAZ!' # if no -foo key is provided, use this
));
-
+
Class::MOP::Attribute->new('$.bar' => (
reader => 'bar', # getter
- writer => 'set_bar', # setter
- predicate => 'has_bar' # predicate check for defined-ness
+ writer => 'set_bar', # setter
+ predicate => 'has_bar' # predicate check for defined-ness
init_arg => ':bar', # class->new will look for a :bar key
# no default value means it is undef
));
=head1 DESCRIPTION
The Attribute Protocol is almost entirely an invention of this module,
-and is completely optional to this MOP. This is because Perl 5 does not
-have consistent notion of what is an attribute of a class. There are
-so many ways in which this is done, and very few (if any) are
+and is completely optional to this MOP. This is because Perl 5 does not
+have consistent notion of what is an attribute of a class. There are
+so many ways in which this is done, and very few (if any) are
easily discoverable by this module.
-So, all that said, this module attempts to inject some order into this
-chaos, by introducing a consistent API which can be used to create
+So, all that said, this module attempts to inject some order into this
+chaos, by introducing a consistent API which can be used to create
object attributes.
=head1 METHODS
=item B<new ($name, ?%options)>
-An attribute must (at the very least), have a C<$name>. All other
+An attribute must (at the very least), have a C<$name>. All other
C<%options> are contained added as key-value pairs. Acceptable keys
are as follows:
=item I<init_arg>
-This should be a string value representing the expected key in
-an initialization hash. For instance, if we have an I<init_arg>
+This should be a string value representing the expected key in
+an initialization hash. For instance, if we have an I<init_arg>
value of C<-foo>, then the following code will Just Work.
MyClass->meta->construct_instance(-foo => "Hello There");
-In an init_arg is not assigned, it will automatically use the
-value of C<$name>.
+In an init_arg is not assigned, it will automatically use the
+value of C<$name>. If an explicit C<undef> is given for an init_arg,
+an attribute value can't be specified during initialization.
+
+=item I<builder>
+
+The value of this key is the name of the method that will be
+called to obtain the value used to initialize the attribute.
+This should be a method in the class associated with the attribute,
+not a method in the attribute class itself.
=item I<default>
-The value of this key is the default value which
-C<Class::MOP::Class::construct_instance> will initialize the
-attribute to.
+The value of this key is the default value which
+C<Class::MOP::Class::construct_instance> will initialize the
+attribute to.
B<NOTE:>
-If the value is a simple scalar (string or number), then it can
-be just passed as is. However, if you wish to initialize it with
-a HASH or ARRAY ref, then you need to wrap that inside a CODE
+If the value is a simple scalar (string or number), then it can
+be just passed as is. However, if you wish to initialize it with
+a HASH or ARRAY ref, then you need to wrap that inside a CODE
reference, like so:
Class::MOP::Attribute->new('@foo' => (
default => sub { [] },
));
-
- # or ...
-
+
+ # or ...
+
Class::MOP::Attribute->new('%foo' => (
default => sub { {} },
- ));
+ ));
-If you wish to initialize an attribute with a CODE reference
+If you wish to initialize an attribute with a CODE reference
itself, then you need to wrap that in a subroutine as well, like
so:
-
+
Class::MOP::Attribute->new('&foo' => (
default => sub { sub { print "Hello World" } },
));
-And lastly, if the value of your attribute is dependent upon
-some other aspect of the instance structure, then you can take
-advantage of the fact that when the I<default> value is a CODE
-reference, it is passed the raw (unblessed) instance structure
+And lastly, if the value of your attribute is dependent upon
+some other aspect of the instance structure, then you can take
+advantage of the fact that when the I<default> value is a CODE
+reference, it is passed the (as yet unfinished) instance structure
as it's only argument. So you can do things like this:
Class::MOP::Attribute->new('$object_identity' => (
default => sub { Scalar::Util::refaddr($_[0]) },
));
-This last feature is fairly limited as there is no gurantee of
-the order of attribute initializations, so you cannot perform
-any kind of dependent initializations. However, if this is
-something you need, you could subclass B<Class::MOP::Class> and
-this class to acheive it. However, this is currently left as
+This last feature is fairly limited as there is no gurantee of
+the order of attribute initializations, so you cannot perform
+any kind of dependent initializations. However, if this is
+something you need, you could subclass B<Class::MOP::Class> and
+this class to acheive it. However, this is currently left as
an exercise to the reader :).
+=item I<initializer>
+
+This may be a method name (referring to a method on the class with this
+attribute) or a CODE ref. The initializer is used to set the attribute value
+on an instance when the attribute is set during instance initialization. When
+called, it is passed the instance (as the invocant), the value to set, a
+slot-setting CODE ref, and the attribute meta-instance. The slot-setting code
+is provided to make it easy to set the (possibly altered) value on the instance
+without going through several more method calls.
+
+This contrived example shows an initializer that sets the attribute to twice
+the given value.
+
+ Class::MOP::Attribute->new('$doubled' => (
+ initializer => sub {
+ my ($instance, $value, $set) = @_;
+ $set->($value * 2);
+ },
+ ));
+
+As method names can be given as initializers, one can easily make
+attribute initialization use the writer:
+
+ Class::MOP::Attribute->new('$some_attr' => (
+ writer => 'some_attr',
+ initializer => 'some_attr',
+ ));
+
+Your writer will simply need to examine it's C<@_> and determine under
+which context it is being called.
+
=back
The I<accessor>, I<reader>, I<writer>, I<predicate> and I<clearer> keys can
=item I<accessor>
-The I<accessor> is a standard perl-style read/write accessor. It will
-return the value of the attribute, and if a value is passed as an argument,
+The I<accessor> is a standard perl-style read/write accessor. It will
+return the value of the attribute, and if a value is passed as an argument,
it will assign that value to the attribute.
B<NOTE:>
-This method will properly handle the following code, by assigning an
+This method will properly handle the following code, by assigning an
C<undef> value to the attribute.
$object->set_something(undef);
=item I<reader>
-This is a basic read-only accessor, it will just return the value of
+This is a basic read-only accessor, it will just return the value of
the attribute.
=item I<writer>
-This is a basic write accessor, it accepts a single argument, and
-assigns that value to the attribute. This method does not intentially
-return a value, however perl will return the result of the last
-expression in the subroutine, which returns in this returning the
-same value that it was passed.
+This is a basic write accessor, it accepts a single argument, and
+assigns that value to the attribute. This method does not intentially
+return a value, however perl will return the result of the last
+expression in the subroutine, which returns in this returning the
+same value that it was passed.
B<NOTE:>
-This method will properly handle the following code, by assigning an
+This method will properly handle the following code, by assigning an
C<undef> value to the attribute.
$object->set_something();
=item I<predicate>
-This is a basic test to see if the value of the attribute is not
-C<undef>. It will return true (C<1>) if the attribute's value is
-defined, and false (C<0>) otherwise.
+This is a basic test to see if any value has been set for the
+attribute. It will return true (C<1>) if the attribute has been set
+to any value (even C<undef>), and false (C<0>) otherwise.
+
+B<NOTE:>
+The predicate will return true even when you set an attribute's
+value to C<undef>. This behaviour has changed as of version 0.43. In
+older versions, the predicate (erroneously) checked for attribute
+value definedness, instead of presence as it is now.
+
+If you really want to get rid of the value, you have to define and
+use a I<clearer> (see below).
=item I<clearer>
=item B<clone (%options)>
+This will return a clone of the attribute instance, allowing the overriding
+of various attributes through the C<%options> supplied.
+
=item B<initialize_instance_slot ($instance, $params)>
-=back
+This method is used internally to initialize the approriate slot for this
+attribute in a given C<$instance>, the C<$params> passed are those that were
+passed to the constructor.
+
+=back
=head2 Value management
+These methods are basically "backdoors" to the instance, which can be used
+to bypass the regular accessors, but still stay within the context of the MOP.
+
+These methods are not for general use, and should only be used if you really
+know what you are doing.
+
=over 4
=item B<set_value ($instance, $value)>
Set the value without going through the accessor. Note that this may be done to
even attributes with just read only accessors.
+=item B<set_initial_value ($instance, $value)>
+
+This method sets the value without going through the accessor -- but it is only
+called when the instance data is first initialized.
+
=item B<get_value ($instance)>
Return the value without going through the accessor. Note that this may be done
=item B<has_value ($instance)>
+Return a boolean indicating if the item in the C<$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
-These are all basic read-only value accessors for the values
+These are all basic read-only value accessors for the values
passed into C<new>. I think they are pretty much self-explanitory.
=over 4
=item B<clearer>
+=item B<initializer>
+
=item B<init_arg>
=item B<is_default_a_coderef>
=item B<default (?$instance)>
-As noted in the documentation for C<new> above, if the I<default>
-value is a CODE reference, this accessor will pass a single additional
-argument C<$instance> into it and return the value.
+Return the default value for the attribute.
+
+If you pass in an C<$instance> argument to this accessor and the
+I<default> is a CODE reference, then the CODE reference will be
+executed with the C<$instance> as its argument.
=item B<slots>
-Returns a list of slots required by the attribute. This is usually
+Return 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 name 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.
+
+=item B<get_read_method_ref>
+
+=item B<get_write_method_ref>
+
+Return the CODE reference 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 specified or not.
+
+NOTE: If no reader/writer/accessor was specified, this will use the
+attribute get_value/set_value methods, which can be very inefficient.
+
+=item B<has_read_method>
+
+=item B<has_write_method>
+
+Return whether a method exists 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
=item B<has_clearer>
+=item B<has_initializer>
+
=item B<has_init_arg>
=item B<has_default>
+=item B<has_builder>
+
=back
=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>
+This returns the metaclass this attribute is associated with.
+
=item B<attach_to_class ($class)>
+This will store a weaken reference to C<$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<$class>. It is up to you to do this manually.
+
=item B<detach_from_class>
+This will remove the weakened reference to the class. It does B<not>
+remove the attribute itself from the class (or remove it's accessors),
+you must do that yourself if you want too. Actually if that is what
+you want to do, you should probably be looking at
+L<Class::MOP::Class::remove_attribute> instead.
+
=back
=head2 Attribute Accessor generation
=item B<accessor_metaclass>
-=item B<associate_method>
+Accessors are generated by an accessor metaclass, which is usually
+a subclass of C<Class::MOP::Method::Accessor>. This method returns
+the name of the accessor metaclass that this attribute uses.
+
+=item B<associate_method ($method)>
+
+This will associate a C<$method> with the given attribute which is
+used internally by the accessor generator.
=item B<associated_methods>
+This will return the list of methods which have been associated with
+the C<associate_method> methods. This is a good way of seeing what
+methods are used to manage a given attribute.
+
=item B<install_accessors>
-This allows the attribute to generate and install code for it's own
-I<accessor/reader/writer/predicate> methods. This is called by
+This allows the attribute to generate and install code for it's own
+I<accessor/reader/writer/predicate> methods. This is called by
C<Class::MOP::Class::add_attribute>.
-This method will call C<process_accessors> for each of the possible
+This method will call C<process_accessors> for each of the possible
method types (accessor, reader, writer & predicate).
=item B<process_accessors ($type, $value)>
-This takes a C<$type> (accessor, reader, writer or predicate), and
+This takes a C<$type> (accessor, reader, writer or predicate), and
a C<$value> (the value passed into the constructor for each of the
-different types). It will then either generate the method itself
-(using the C<generate_*_method> methods listed below) or it will
-use the custom method passed through the constructor.
+different types). It will then either generate the method itself
+(using the C<generate_*_method> methods listed below) or it will
+use the custom method passed through the constructor.
=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
+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
=item B<meta>
-This will return a B<Class::MOP::Class> instance which is related
+This will return a B<Class::MOP::Class> instance which is related
to this class.
-It should also be noted that B<Class::MOP> will actually bootstrap
-this module by installing a number of attribute meta-objects into
-it's metaclass. This will allow this class to reap all the benifits
-of the MOP when subclassing it.
+It should also be noted that B<Class::MOP> will actually bootstrap
+this module by installing a number of attribute meta-objects into
+it's metaclass. This will allow this class to reap all the benefits
+of the MOP when subclassing it.
=back
Stevan Little E<lt>stevan@iinteractive.comE<gt>
-Yuval Kogman E<lt>nothingmuch@woobling.comE<gt>
-
=head1 COPYRIGHT AND LICENSE
-Copyright 2006 by Infinity Interactive, Inc.
+Copyright 2006-2008 by Infinity Interactive, Inc.
L<http://www.iinteractive.com>
This library is free software; you can redistribute it and/or modify
-it under the same terms as Perl itself.
+it under the same terms as Perl itself.
=cut
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