use Carp 'confess';
use Scalar::Util 'blessed';
-our $VERSION = '0.01';
+our $VERSION = '0.73';
+$VERSION = eval $VERSION;
our $AUTHORITY = 'cpan:STEVAN';
-sub new {
- my ($class, $metaclass, $options) = @_;
-
- my $self = bless {
- metaclass => $metaclass,
- options => $options,
- immutable_metaclass => undef,
- } => $class;
-
- # NOTE:
- # we initialize the immutable
- # version of the metaclass here
- $self->create_immutable_metaclass;
-
+use base 'Class::MOP::Object';
+
+sub new {
+ my ($class, @args) = @_;
+
+ my ( $metaclass, $options );
+
+ if ( @args == 2 ) {
+ # compatibility args
+ ( $metaclass, $options ) = @args;
+ } else {
+ unshift @args, "metaclass" if @args % 2 == 1;
+
+ # default named args
+ my %options = @args;
+ $options = \%options;
+ $metaclass = $options{metaclass};
+ }
+
+ my $self = $class->_new(
+ 'metaclass' => $metaclass,
+ 'options' => $options,
+ 'immutable_metaclass' => undef,
+ 'inlined_constructor' => undef,
+ );
+
return $self;
}
-sub immutable_metaclass { (shift)->{immutable_metaclass} }
-sub metaclass { (shift)->{metaclass} }
-sub options { (shift)->{options} }
+sub _new {
+ my $class = shift;
+ my $options = @_ == 1 ? $_[0] : {@_};
+
+ bless $options, $class;
+}
+
+sub immutable_metaclass {
+ my $self = shift;
+
+ $self->create_immutable_metaclass unless $self->{'immutable_metaclass'};
+
+ return $self->{'immutable_metaclass'};
+}
+
+sub metaclass { (shift)->{'metaclass'} }
+sub options { (shift)->{'options'} }
+sub inlined_constructor { (shift)->{'inlined_constructor'} }
sub create_immutable_metaclass {
my $self = shift;
# NOTE:
- # The immutable version of the
+ # The immutable version of the
# metaclass is just a anon-class
- # which shadows the methods
+ # which shadows the methods
# appropriately
- $self->{immutable_metaclass} = Class::MOP::Class->create_anon_class(
+ $self->{'immutable_metaclass'} = Class::MOP::Class->create_anon_class(
superclasses => [ blessed($self->metaclass) ],
methods => $self->create_methods_for_immutable_metaclass,
- );
+ );
}
+
my %DEFAULT_METHODS = (
- meta => sub {
+ # I don't really understand this, but removing it breaks tests (groditi)
+ meta => sub {
my $self = shift;
- # if it is not blessed, then someone is asking
- # for the meta of Class::MOP::Class::Immutable
+ # if it is not blessed, then someone is asking
+ # for the meta of Class::MOP::Immutable
return Class::MOP::Class->initialize($self) unless blessed($self);
- # otherwise, they are asking for the metaclass
+ # otherwise, they are asking for the metaclass
# which has been made immutable, which is itself
- return $self;
+ # except in the cases where it is a metaclass itself
+ # that has been made immutable and for that we need
+ # to dig a bit ...
+ if ($self->isa('Class::MOP::Class')) {
+ return $self->{'___original_class'}->meta;
+ }
+ else {
+ return $self;
+ }
},
- is_mutable => sub { 0 },
- is_immutable => sub { 1 },
- make_immutable => sub { ( ) },
+ is_mutable => sub { 0 },
+ is_immutable => sub { 1 },
+ make_immutable => sub { () },
);
# NOTE:
-# this will actually convert the
-# existing metaclass to an immutable
+# this will actually convert the
+# existing metaclass to an immutable
# version of itself
sub make_metaclass_immutable {
- my ($self, $metaclass, %options) = @_;
-
- $options{inline_accessors} = 1 unless exists $options{inline_accessors};
- $options{inline_constructor} = 1 unless exists $options{inline_constructor};
- $options{constructor_name} = 'new' unless exists $options{constructor_name};
- $options{debug} = 0 unless exists $options{debug};
-
- if ($options{inline_accessors}) {
- foreach my $attr_name ($metaclass->get_attribute_list) {
- # inline the accessors
- $metaclass->get_attribute($attr_name)
- ->install_accessors(1);
- }
+ my ($self, $metaclass, $options) = @_;
+
+ my %options = (
+ inline_accessors => 1,
+ inline_constructor => 1,
+ inline_destructor => 0,
+ constructor_name => 'new',
+ debug => 0,
+ %$options,
+ );
+
+ %$options = %options; # FIXME who the hell is relying on this?!? tests fail =(
+
+ $self->_inline_accessors( $metaclass, \%options );
+ $self->_inline_constructor( $metaclass, \%options );
+ $self->_inline_destructor( $metaclass, \%options );
+ $self->_check_memoized_methods( $metaclass, \%options );
+
+ $metaclass->{'___original_class'} = blessed($metaclass);
+ bless $metaclass => $self->immutable_metaclass->name;
+}
+
+sub _inline_accessors {
+ my ( $self, $metaclass, $options ) = @_;
+
+ return unless $options->{inline_accessors};
+
+ foreach my $attr_name ( $metaclass->get_attribute_list ) {
+ $metaclass->get_attribute($attr_name)->install_accessors(1);
}
+}
+
+sub _inline_constructor {
+ my ( $self, $metaclass, $options ) = @_;
+
+ return unless $options->{inline_constructor};
+
+ return
+ unless $options->{replace_constructor}
+ or !$metaclass->has_method( $options->{constructor_name} );
+
+ my $constructor_class = $options->{constructor_class}
+ || 'Class::MOP::Method::Constructor';
+
+ my $constructor = $constructor_class->new(
+ options => $options,
+ metaclass => $metaclass,
+ is_inline => 1,
+ package_name => $metaclass->name,
+ name => $options->{constructor_name},
+ );
+
+ if ( $options->{replace_constructor} or $constructor->can_be_inlined ) {
+ $metaclass->add_method( $options->{constructor_name} => $constructor );
+ $self->{inlined_constructor} = $constructor;
+ }
+}
+
+sub _inline_destructor {
+ my ( $self, $metaclass, $options ) = @_;
+
+ return unless $options->{inline_destructor};
+
+ ( exists $options->{destructor_class} )
+ || confess "The 'inline_destructor' option is present, but "
+ . "no destructor class was specified";
+
+ my $destructor_class = $options->{destructor_class};
+
+ return unless $destructor_class->is_needed($metaclass);
+
+ my $destructor = $destructor_class->new(
+ options => $options,
+ metaclass => $metaclass,
+ package_name => $metaclass->name,
+ name => 'DESTROY'
+ );
+
+ return unless $destructor->is_needed;
+
+ $metaclass->add_method( 'DESTROY' => $destructor )
+}
+
+sub _check_memoized_methods {
+ my ( $self, $metaclass, $options ) = @_;
- if ($options{inline_constructor}) {
- my $constructor_class = $options{constructor_class} || 'Class::MOP::Method::Constructor';
-
- my $constructor = $constructor_class->new(
- options => \%options,
- meta_instance => $metaclass->get_meta_instance,
- attributes => [ $metaclass->compute_all_applicable_attributes ]
- );
-
- $metaclass->add_method(
- $options{constructor_name},
- $constructor
- );
- }
-
my $memoized_methods = $self->options->{memoize};
- foreach my $method_name (keys %{$memoized_methods}) {
+ foreach my $method_name ( keys %{$memoized_methods} ) {
my $type = $memoized_methods->{$method_name};
-
- ($metaclass->can($method_name))
- || confess "Could not find the method '$method_name' in " . $metaclass->name;
-
- my $memoized_method;
- if ($type eq 'ARRAY') {
- $metaclass->{'___' . $method_name} = [ $metaclass->$method_name ];
- }
- elsif ($type eq 'HASH') {
- $metaclass->{'___' . $method_name} = { $metaclass->$method_name };
- }
- elsif ($type eq 'SCALAR') {
- $metaclass->{'___' . $method_name} = $metaclass->$method_name;
- }
- }
- $metaclass->{'___original_class'} = blessed($metaclass);
- bless $metaclass => $self->immutable_metaclass->name;
+ ( $metaclass->can($method_name) )
+ || confess "Could not find the method '$method_name' in "
+ . $metaclass->name;
+ }
}
sub create_methods_for_immutable_metaclass {
my $self = shift;
-
- my %methods = %DEFAULT_METHODS;
-
- foreach my $read_only_method (@{$self->options->{read_only}}) {
- my $method = $self->metaclass->meta->find_method_by_name($read_only_method);
-
- (defined $method)
- || confess "Could not find the method '$read_only_method' in " . $self->metaclass->name;
-
+
+ my %methods = %DEFAULT_METHODS;
+ my $metaclass = $self->metaclass;
+ my $meta = $metaclass->meta;
+
+ $methods{get_mutable_metaclass_name}
+ = sub { (shift)->{'___original_class'} };
+
+ $methods{immutable_transformer} = sub {$self};
+
+ return {
+ %DEFAULT_METHODS,
+ $self->_make_read_only_methods( $metaclass, $meta ),
+ $self->_make_uncallable_methods( $metaclass, $meta ),
+ $self->_make_memoized_methods( $metaclass, $meta ),
+ $self->_make_wrapped_methods( $metaclass, $meta ),
+ get_mutable_metaclass_name => sub { (shift)->{'___original_class'} },
+ immutable_transformer => sub {$self},
+ };
+}
+
+sub _make_read_only_methods {
+ my ( $self, $metaclass, $meta ) = @_;
+
+ my %methods;
+ foreach my $read_only_method ( @{ $self->options->{read_only} } ) {
+ my $method = $meta->find_method_by_name($read_only_method);
+
+ ( defined $method )
+ || confess "Could not find the method '$read_only_method' in "
+ . $metaclass->name;
+
$methods{$read_only_method} = sub {
confess "This method is read-only" if scalar @_ > 1;
- goto &{$method->body}
+ goto &{ $method->body };
};
}
-
- foreach my $cannot_call_method (@{$self->options->{cannot_call}}) {
+
+ return %methods;
+}
+
+sub _make_uncallable_methods {
+ my ( $self, $metaclass, $meta ) = @_;
+
+ my %methods;
+ foreach my $cannot_call_method ( @{ $self->options->{cannot_call} } ) {
$methods{$cannot_call_method} = sub {
- confess "This method cannot be called on an immutable instance";
+ confess
+ "This method ($cannot_call_method) cannot be called on an immutable instance";
};
- }
-
+ }
+
+ return %methods;
+}
+
+sub _make_memoized_methods {
+ my ( $self, $metaclass, $meta ) = @_;
+
+ my %methods;
+
+ my $memoized_methods = $self->options->{memoize};
+ foreach my $method_name ( keys %{$memoized_methods} ) {
+ my $type = $memoized_methods->{$method_name};
+ my $key = '___' . $method_name;
+ my $method = $meta->find_method_by_name($method_name);
+
+ if ( $type eq 'ARRAY' ) {
+ $methods{$method_name} = sub {
+ @{ $_[0]->{$key} } = $method->execute( $_[0] )
+ if !exists $_[0]->{$key};
+ return @{ $_[0]->{$key} };
+ };
+ }
+ elsif ( $type eq 'HASH' ) {
+ $methods{$method_name} = sub {
+ %{ $_[0]->{$key} } = $method->execute( $_[0] )
+ if !exists $_[0]->{$key};
+ return %{ $_[0]->{$key} };
+ };
+ }
+ elsif ( $type eq 'SCALAR' ) {
+ $methods{$method_name} = sub {
+ $_[0]->{$key} = $method->execute( $_[0] )
+ if !exists $_[0]->{$key};
+ return $_[0]->{$key};
+ };
+ }
+ }
+
+ return %methods;
+}
+
+sub _make_wrapped_methods {
+ my ( $self, $metaclass, $meta ) = @_;
+
+ my %methods;
+
+ my $wrapped_methods = $self->options->{wrapped};
+
+ foreach my $method_name ( keys %{$wrapped_methods} ) {
+ my $method = $meta->find_method_by_name($method_name);
+
+ ( defined $method )
+ || confess "Could not find the method '$method_name' in "
+ . $metaclass->name;
+
+ my $wrapper = $wrapped_methods->{$method_name};
+
+ $methods{$method_name} = sub { $wrapper->( $method, @_ ) };
+ }
+
+ return %methods;
+}
+
+sub make_metaclass_mutable {
+ my ($self, $immutable, $options) = @_;
+
+ my %options = %$options;
+
+ my $original_class = $immutable->get_mutable_metaclass_name;
+ delete $immutable->{'___original_class'} ;
+ bless $immutable => $original_class;
+
my $memoized_methods = $self->options->{memoize};
-
foreach my $method_name (keys %{$memoized_methods}) {
my $type = $memoized_methods->{$method_name};
- if ($type eq 'ARRAY') {
- $methods{$method_name} = sub { @{$_[0]->{'___' . $method_name}} };
+
+ ($immutable->can($method_name))
+ || confess "Could not find the method '$method_name' in " . $immutable->name;
+ if ($type eq 'SCALAR' || $type eq 'ARRAY' || $type eq 'HASH' ) {
+ delete $immutable->{'___' . $method_name};
}
- elsif ($type eq 'HASH') {
- $methods{$method_name} = sub { %{$_[0]->{'___' . $method_name}} };
+ }
+
+ if ($options{inline_destructor} && $immutable->has_method('DESTROY')) {
+ $immutable->remove_method('DESTROY')
+ if blessed($immutable->get_method('DESTROY')) eq $options{destructor_class};
+ }
+
+ # NOTE:
+ # 14:01 <@stevan> nah,. you shouldnt
+ # 14:01 <@stevan> they are just inlined
+ # 14:01 <@stevan> which is the default in Moose anyway
+ # 14:02 <@stevan> and adding new attributes will just DWIM
+ # 14:02 <@stevan> and you really cant change an attribute anyway
+ # if ($options{inline_accessors}) {
+ # foreach my $attr_name ($immutable->get_attribute_list) {
+ # my $attr = $immutable->get_attribute($attr_name);
+ # $attr->remove_accessors;
+ # $attr->install_accessors(0);
+ # }
+ # }
+
+ # 14:26 <@stevan> the only user of ::Method::Constructor is immutable
+ # 14:27 <@stevan> if someone uses it outside of immutable,.. they are either: mst or groditi
+ # 14:27 <@stevan> so I am not worried
+ if ($options{inline_constructor} && $immutable->has_method($options{constructor_name})) {
+ my $constructor_class = $options{constructor_class} || 'Class::MOP::Method::Constructor';
+
+ if ( blessed($immutable->get_method($options{constructor_name})) eq $constructor_class ) {
+ $immutable->remove_method( $options{constructor_name} );
+ $self->{inlined_constructor} = undef;
}
- elsif ($type eq 'SCALAR') {
- $methods{$method_name} = sub { $_[0]->{'___' . $method_name} };
- }
- }
-
- $methods{get_mutable_metaclass_name} = sub { (shift)->{'___original_class'} };
-
- return \%methods;
+ }
}
1;
=pod
-=head1 NAME
+=head1 NAME
Class::MOP::Immutable - A class to transform Class::MOP::Class metaclasses
=head1 SYNOPSIS
+ use Class::MOP::Immutable;
+
+ my $immutable_metaclass = Class::MOP::Immutable->new($metaclass, {
+ read_only => [qw/superclasses/],
+ cannot_call => [qw/
+ add_method
+ alias_method
+ remove_method
+ add_attribute
+ remove_attribute
+ add_package_symbol
+ remove_package_symbol
+ /],
+ memoize => {
+ class_precedence_list => 'ARRAY',
+ compute_all_applicable_attributes => 'ARRAY',
+ get_meta_instance => 'SCALAR',
+ get_method_map => 'SCALAR',
+ }
+ });
+
+ $immutable_metaclass->make_metaclass_immutable(@_)
+
=head1 DESCRIPTION
+This is basically a module for applying a transformation on a given
+metaclass. Current features include making methods read-only,
+making methods un-callable and memoizing methods (in a type specific
+way too).
+
+This module is not for the feint of heart, it does some whacky things
+to the metaclass in order to make it immutable. If you are just curious,
+I suggest you turn back now, there is nothing to see here.
+
=head1 METHODS
=over 4
-=item B<new>
-
+=item B<new ($metaclass, \%options)>
+
+Given a C<$metaclass> and a set of C<%options> this module will
+prepare an immutable version of the C<$metaclass>, which can then
+be applied to the C<$metaclass> using the C<make_metaclass_immutable>
+method.
+
=item B<options>
+Returns the options HASH set in C<new>.
+
=item B<metaclass>
+Returns the metaclass set in C<new>.
+
=item B<immutable_metaclass>
+Returns the immutable metaclass created within C<new>.
+
=back
=over 4
=item B<create_immutable_metaclass>
+This will create the immutable version of the C<$metaclass>, but will
+not actually change the original metaclass.
+
=item B<create_methods_for_immutable_metaclass>
-=item B<make_metaclass_immutable>
+This will create all the methods for the immutable metaclass based
+on the C<%options> passed into C<new>.
+
+=item B<make_metaclass_immutable (%options)>
+
+This will actually change the C<$metaclass> into the immutable version.
+
+=item B<make_metaclass_mutable (%options)>
+
+This will change the C<$metaclass> into the mutable version by reversing
+the immutable process. C<%options> should be the same options that were
+given to make_metaclass_immutable.
+
+=item B<inlined_constructor>
+
+If the constructor was inlined, this returns the constructor method
+object that was created to do this.
=back
=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
projects / gitmo/Class-MOP.git / blobdiff