use Carp 'confess';
use Scalar::Util 'blessed', 'reftype', 'weaken';
use Sub::Name 'subname';
-use B 'svref_2object';
-our $VERSION = '0.22';
+our $VERSION = '0.28';
our $AUTHORITY = 'cpan:STEVAN';
use base 'Class::MOP::Module';
my $package_name = shift;
(defined $package_name && $package_name && !blessed($package_name))
|| confess "You must pass a package name and it cannot be blessed";
+ if (defined(my $meta = Class::MOP::get_metaclass_by_name($package_name))) {
+ return $meta;
+ }
$class->construct_class_instance('package' => $package_name, @_);
}
# and it is still defined (it has not been
# reaped by DESTROY yet, which can happen
# annoyingly enough during global destruction)
- return Class::MOP::get_metaclass_by_name($package_name)
- if Class::MOP::does_metaclass_exist($package_name);
+
+ if (defined(my $meta = Class::MOP::get_metaclass_by_name($package_name))) {
+ return $meta;
+ }
# NOTE:
# we need to deal with the possibility
# now create the metaclass
my $meta;
- if ($class =~ /^Class::MOP::Class$/) {
+ if ($class eq 'Class::MOP::Class') {
no strict 'refs';
$meta = bless {
# inherited from Class::MOP::Package
'$!attribute_metaclass' => $options{'attribute_metaclass'} || 'Class::MOP::Attribute',
'$!method_metaclass' => $options{'method_metaclass'} || 'Class::MOP::Method',
'$!instance_metaclass' => $options{'instance_metaclass'} || 'Class::MOP::Instance',
+
+ ## uber-private variables
+ # NOTE:
+ # this starts out as undef so that
+ # we can tell the first time the
+ # methods are fetched
+ # - SL
+ '$!_package_cache_flag' => undef,
} => $class;
}
else {
}
# and check the metaclass compatibility
- $meta->check_metaclass_compatability();
+ $meta->check_metaclass_compatability();
Class::MOP::store_metaclass_by_name($package_name, $meta);
$meta;
}
+sub reset_package_cache_flag { (shift)->{'$!_package_cache_flag'} = undef }
+sub update_package_cache_flag {
+ my $self = shift;
+ # NOTE:
+ # we can manually update the cache number
+ # since we are actually adding the method
+ # to our cache as well. This avoids us
+ # having to regenerate the method_map.
+ # - SL
+ $self->{'$!_package_cache_flag'} = Class::MOP::check_package_cache_flag($self->name);
+}
+
sub check_metaclass_compatability {
my $self = shift;
return if blessed($self) eq 'Class::MOP::Class' &&
$self->instance_metaclass eq 'Class::MOP::Instance';
- my @class_list = $self->class_precedence_list;
+ my @class_list = $self->linearized_isa;
shift @class_list; # shift off $self->name
foreach my $class_name (@class_list) {
# this is a prime canidate for conversion to XS
sub get_method_map {
my $self = shift;
+
+ if (defined $self->{'$!_package_cache_flag'} &&
+ $self->{'$!_package_cache_flag'} == Class::MOP::check_package_cache_flag($self->name)) {
+ return $self->{'%!methods'};
+ }
+
my $map = $self->{'%!methods'};
my $class_name = $self->name;
defined $map->{$symbol} &&
$map->{$symbol}->body == $code;
- my $gv = svref_2object($code)->GV;
- next if ($gv->STASH->NAME || '') ne $class_name &&
- ($gv->NAME || '') ne '__ANON__';
+ my ($pkg, $name) = Class::MOP::get_code_info($code);
+ next if ($pkg || '') ne $class_name &&
+ ($name || '') ne '__ANON__';
$map->{$symbol} = $method_metaclass->wrap($code);
}
my $meta_instance = $class->get_meta_instance();
my $clone = $meta_instance->clone_instance($instance);
foreach my $attr ($class->compute_all_applicable_attributes()) {
- if (exists $params{$attr->init_arg}) {
- $meta_instance->set_slot_value($clone, $attr->name, $params{$attr->init_arg});
+ if ( defined( my $init_arg = $attr->init_arg ) ) {
+ if (exists $params{$init_arg}) {
+ $attr->set_value($clone, $params{$init_arg});
+ }
}
}
return $clone;
}
+sub rebless_instance {
+ my ($self, $instance) = @_;
+
+ my $old_metaclass;
+ if ($instance->can('meta')) {
+ ($instance->meta->isa('Class::MOP::Class'))
+ || confess 'Cannot rebless instance if ->meta is not an instance of Class::MOP::Class';
+ $old_metaclass = $instance->meta;
+ }
+ else {
+ $old_metaclass = $self->initialize(blessed($instance));
+ }
+
+ my $meta_instance = $self->get_meta_instance();
+
+ $self->name->isa($old_metaclass->name)
+ || confess "You may rebless only into a subclass of (". $old_metaclass->name ."), of which (". $self->name .") isn't.";
+
+ # rebless!
+ $meta_instance->rebless_instance_structure($instance, $self);
+
+ my %params;
+
+ foreach my $attr ( $self->compute_all_applicable_attributes ) {
+ if ( $attr->has_value($instance) ) {
+ if ( defined( my $init_arg = $attr->init_arg ) ) {
+ $params{$init_arg} = $attr->get_value($instance);
+ } else {
+ $attr->set_value($instance);
+ }
+ }
+ }
+
+ foreach my $attr ($self->compute_all_applicable_attributes) {
+ $attr->initialize_instance_slot($meta_instance, $instance, \%params);
+ }
+}
+
+sub get_attribute_values {
+ my ($self, $instance) = @_;
+
+ return +{
+ map { $_->name => $_->get_value($instance) }
+ grep { $_->has_value($instance) }
+ $self->compute_all_applicable_attributes
+ };
+}
+
+sub get_init_args {
+ my ($self, $instance) = @_;
+
+ return +{
+ map { $_->init_arg => $_->get_value($instance) }
+ grep { $_->has_value($instance) }
+ grep { defined($_->init_arg) }
+ $self->compute_all_applicable_attributes
+ };
+}
+
# Inheritance
sub superclasses {
@{$self->get_package_symbol('@ISA')} = @supers;
# NOTE:
# we need to check the metaclass
- # compatability here so that we can
+ # compatibility here so that we can
# be sure that the superclass is
# not potentially creating an issues
# we don't know about
@{$self->get_package_symbol('@ISA')};
}
+sub subclasses {
+ my $self = shift;
+
+ my $super_class = $self->name;
+ my @derived_classes;
+
+ my $find_derived_classes;
+ $find_derived_classes = sub {
+ my ($outer_class) = @_;
+
+ my $symbol_table_hashref = do { no strict 'refs'; \%{"${outer_class}::"} };
+
+ SYMBOL:
+ for my $symbol ( keys %$symbol_table_hashref ) {
+ next SYMBOL if $symbol !~ /\A (\w+):: \z/x;
+ my $inner_class = $1;
+
+ next SYMBOL if $inner_class eq 'SUPER'; # skip '*::SUPER'
+
+ my $class =
+ $outer_class
+ ? "${outer_class}::$inner_class"
+ : $inner_class;
+
+ if ( $class->isa($super_class) and $class ne $super_class ) {
+ push @derived_classes, $class;
+ }
+
+ next SYMBOL if $class eq 'main'; # skip 'main::*'
+
+ $find_derived_classes->($class);
+ }
+ };
+
+ my $root_class = q{};
+ $find_derived_classes->($root_class);
+
+ undef $find_derived_classes;
+
+ @derived_classes = sort { $a->isa($b) ? 1 : $b->isa($a) ? -1 : 0 } @derived_classes;
+
+ return @derived_classes;
+}
+
+
+sub linearized_isa {
+ if (Class::MOP::IS_RUNNING_ON_5_10()) {
+ return @{ mro::get_linear_isa( (shift)->name ) };
+ }
+ else {
+ my %seen;
+ return grep { !($seen{$_}++) } (shift)->class_precedence_list;
+ }
+}
+
sub class_precedence_list {
my $self = shift;
- # NOTE:
- # We need to check for ciruclar inheirtance here.
- # This will do nothing if all is well, and blow
- # up otherwise. Yes, it's an ugly hack, better
- # suggestions are welcome.
- { ($self->name || return)->isa('This is a test for circular inheritance') }
+
+ unless (Class::MOP::IS_RUNNING_ON_5_10()) {
+ # NOTE:
+ # We need to check for circular inheritance here
+ # if we are are not on 5.10, cause 5.8 detects it
+ # late. This will do nothing if all is well, and
+ # blow up otherwise. Yes, it's an ugly hack, better
+ # suggestions are welcome.
+ # - SL
+ ($self->name || return)->isa('This is a test for circular inheritance')
+ }
(
$self->name,
my $full_method_name = ($self->name . '::' . $method_name);
$self->add_package_symbol("&${method_name}" => subname $full_method_name => $body);
+ $self->update_package_cache_flag;
}
{
|| confess "Your code block must be a CODE reference";
$self->add_package_symbol("&${method_name}" => $body);
+ $self->update_package_cache_flag;
}
sub has_method {
(defined $method_name && $method_name)
|| confess "You must define a method name";
- my $removed_method = $self->get_method($method_name);
-
- do {
- $self->remove_package_symbol("&${method_name}");
- delete $self->get_method_map->{$method_name};
- } if defined $removed_method;
+ my $removed_method = delete $self->get_method_map->{$method_name};
+
+ $self->remove_package_symbol("&${method_name}");
+
+ $self->update_package_cache_flag;
return $removed_method;
}
my ($self, $method_name) = @_;
(defined $method_name && $method_name)
|| confess "You must define a method name to find";
- # keep a record of what we have seen
- # here, this will handle all the
- # inheritence issues because we are
- # using the &class_precedence_list
- my %seen_class;
- my @cpl = $self->class_precedence_list();
- foreach my $class (@cpl) {
- next if $seen_class{$class};
- $seen_class{$class}++;
+ foreach my $class ($self->linearized_isa) {
# fetch the meta-class ...
my $meta = $self->initialize($class);
return $meta->get_method($method_name)
sub compute_all_applicable_methods {
my $self = shift;
- my @methods;
- # keep a record of what we have seen
- # here, this will handle all the
- # inheritence issues because we are
- # using the &class_precedence_list
- my (%seen_class, %seen_method);
- foreach my $class ($self->class_precedence_list()) {
- next if $seen_class{$class};
- $seen_class{$class}++;
+ my (@methods, %seen_method);
+ foreach my $class ($self->linearized_isa) {
# fetch the meta-class ...
my $meta = $self->initialize($class);
foreach my $method_name ($meta->get_method_list()) {
(defined $method_name && $method_name)
|| confess "You must define a method name to find";
my @methods;
- # keep a record of what we have seen
- # here, this will handle all the
- # inheritence issues because we are
- # using the &class_precedence_list
- my %seen_class;
- foreach my $class ($self->class_precedence_list()) {
- next if $seen_class{$class};
- $seen_class{$class}++;
+ foreach my $class ($self->linearized_isa) {
# fetch the meta-class ...
my $meta = $self->initialize($class);
push @methods => {
my ($self, $method_name) = @_;
(defined $method_name && $method_name)
|| confess "You must define a method name to find";
- # keep a record of what we have seen
- # here, this will handle all the
- # inheritence issues because we are
- # using the &class_precedence_list
- my %seen_class;
- my @cpl = $self->class_precedence_list();
+ my @cpl = $self->linearized_isa;
shift @cpl; # discard ourselves
foreach my $class (@cpl) {
- next if $seen_class{$class};
- $seen_class{$class}++;
# fetch the meta-class ...
my $meta = $self->initialize($class);
return $meta->get_method($method_name)
sub compute_all_applicable_attributes {
my $self = shift;
- my @attrs;
- # keep a record of what we have seen
- # here, this will handle all the
- # inheritence issues because we are
- # using the &class_precedence_list
- my (%seen_class, %seen_attr);
- foreach my $class ($self->class_precedence_list()) {
- next if $seen_class{$class};
- $seen_class{$class}++;
+ my (@attrs, %seen_attr);
+ foreach my $class ($self->linearized_isa) {
# fetch the meta-class ...
my $meta = $self->initialize($class);
foreach my $attr_name ($meta->get_attribute_list()) {
sub find_attribute_by_name {
my ($self, $attr_name) = @_;
- # keep a record of what we have seen
- # here, this will handle all the
- # inheritence issues because we are
- # using the &class_precedence_list
- my %seen_class;
- foreach my $class ($self->class_precedence_list()) {
- next if $seen_class{$class};
- $seen_class{$class}++;
+ foreach my $class ($self->linearized_isa) {
# fetch the meta-class ...
my $meta = $self->initialize($class);
return $meta->get_attribute($attr_name)
sub is_mutable { 1 }
sub is_immutable { 0 }
-#Why I changed this (groditi)
-# - One Metaclass may have many Classes through many Metaclass instances
-# - One Metaclass should only have one Immutable Transformer instance
-# - Each Class may have different Immutabilizing options
-# - Therefore each Metaclass instance may have different Immutabilizing options
-# - We need to store one Immutable Transformer instance per Metaclass
-# - We need to store one set of Immutable Transformer options per Class
-# - Upon make_mutable we may delete the Immutabilizing options
-# - We could clean the immutable Transformer instance when there is no more
-# immutable Classes of that type, but we can also keep it in case
-# another class with this same Metaclass becomes immutable. It is a case
-# of trading of storing an instance to avoid unnecessary instantiations of
-# Immutable Transformers. You may view this as a memory leak, however
-# Because we have few Metaclasses, in practice it seems acceptable
-# - To allow Immutable Transformers instances to be cleaned up we could weaken
-# the reference stored in $IMMUTABLE_TRANSFORMERS{$class} and ||= should DWIM
+# NOTE:
+# Why I changed this (groditi)
+# - One Metaclass may have many Classes through many Metaclass instances
+# - One Metaclass should only have one Immutable Transformer instance
+# - Each Class may have different Immutabilizing options
+# - Therefore each Metaclass instance may have different Immutabilizing options
+# - We need to store one Immutable Transformer instance per Metaclass
+# - We need to store one set of Immutable Transformer options per Class
+# - Upon make_mutable we may delete the Immutabilizing options
+# - We could clean the immutable Transformer instance when there is no more
+# immutable Classes of that type, but we can also keep it in case
+# another class with this same Metaclass becomes immutable. It is a case
+# of trading of storing an instance to avoid unnecessary instantiations of
+# Immutable Transformers. You may view this as a memory leak, however
+# Because we have few Metaclasses, in practice it seems acceptable
+# - To allow Immutable Transformers instances to be cleaned up we could weaken
+# the reference stored in $IMMUTABLE_TRANSFORMERS{$class} and ||= should DWIM
{
my %IMMUTABLE_TRANSFORMERS;
$IMMUTABLE_TRANSFORMERS{$class} ||= $self->create_immutable_transformer;
my $transformer = $IMMUTABLE_TRANSFORMERS{$class};
- $transformer->make_metaclass_immutable($self, %options);
+ $transformer->make_metaclass_immutable($self, \%options);
$IMMUTABLE_OPTIONS{$self->name} =
{ %options, IMMUTABLE_TRANSFORMER => $transformer };
my $self = shift;
return if $self->is_mutable;
my $options = delete $IMMUTABLE_OPTIONS{$self->name};
- confess "unable to find immutabilizing options" unless $options;
+ confess "unable to find immutabilizing options" unless ref $options;
my $transformer = delete $options->{IMMUTABLE_TRANSFORMER};
- $transformer->make_metaclass_mutable($self, %$options);
+ $transformer->make_metaclass_mutable($self, $options);
}
}
/],
memoize => {
class_precedence_list => 'ARRAY',
+ linearized_isa => 'ARRAY',
compute_all_applicable_attributes => 'ARRAY',
get_meta_instance => 'SCALAR',
get_method_map => 'SCALAR',
your ancestors. For more inforamtion about metaclass compatibility
see the C<About Metaclass compatibility> section in L<Class::MOP>.
+=item B<update_package_cache_flag>
+
+This will reset the package cache flag for this particular metaclass
+it is basically the value of the C<Class::MOP::get_package_cache_flag>
+function. This is very rarely needed from outside of C<Class::MOP::Class>
+but in some cases you might want to use it, so it is here.
+
+=item B<reset_package_cache_flag>
+
+Clear this flag, used in Moose.
+
=back
=head2 Object instance construction and cloning
think Yuval "nothingmuch" Kogman put it best when he said that cloning
is too I<context-specific> to be part of the MOP.
+=item B<get_attribute_values($instance)>
+
+Returns the values of the C<$instance>'s fields keyed by the attribute names.
+
+=item B<get_init_args($instance)>
+
+Returns a hash reference where the keys are all the attributes' C<init_arg>s
+and the values are the instance's fields. Attributes without an C<init_arg>
+will be skipped.
+
+=item B<rebless_instance($instance)>
+
+This will change the class of C<$instance> to the class of the invoking
+C<Class::MOP::Class>. You may only rebless the instance to a subclass of
+itself. This limitation may be relaxed in the future.
+
+This can be useful in a number of situations, such as when you are writing
+a program that doesn't know everything at object construction time.
+
=back
=head2 Informational
in which method dispatch will be done. This is similair to
what B<Class::ISA::super_path> does, but we don't remove duplicate names.
+=item B<linearized_isa>
+
+This returns a list based on C<class_precedence_list> but with all
+duplicates removed.
+
+=item B<subclasses>
+
+This returns a list of subclasses for this class.
+
=back
=head2 Methods
This method will reverse tranforamtion upon the class which
made it immutable.
+=item B<create_immutable_transformer>
+
+Create a transformer suitable for making this class immutable
+
=back
=head1 AUTHORS
=head1 COPYRIGHT AND LICENSE
-Copyright 2006, 2007 by Infinity Interactive, Inc.
+Copyright 2006-2008 by Infinity Interactive, Inc.
L<http://www.iinteractive.com>