X-Git-Url: http://git.shadowcat.co.uk/gitweb/gitweb.cgi?a=blobdiff_plain;f=lib%2FClass%2FMOP%2FImmutable.pm;h=9b96087c5b0954d969326f6bdc1a943dc91b89d8;hb=f3ddcd1a0bcb963fc368a7f7fcbd1cf76c515ed0;hp=851cdafdb7b9077cc9cdb121aa8f1d662cdaa60e;hpb=ec845081066fd7944a963fbc1e63b5d42f609589;p=gitmo%2FClass-MOP.git diff --git a/lib/Class/MOP/Immutable.pm b/lib/Class/MOP/Immutable.pm index 851cdaf..9b96087 100644 --- a/lib/Class/MOP/Immutable.pm +++ b/lib/Class/MOP/Immutable.pm @@ -9,7 +9,7 @@ use Class::MOP::Method::Constructor; use Carp 'confess'; use Scalar::Util 'blessed'; -our $VERSION = '0.71_01'; +our $VERSION = '0.80'; $VERSION = eval $VERSION; our $AUTHORITY = 'cpan:STEVAN'; @@ -18,23 +18,21 @@ use base 'Class::MOP::Object'; sub new { my ($class, @args) = @_; - my ( $metaclass, $options ); + unshift @args, 'metaclass' if @args % 2 == 1; - 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 %options = ( + inline_accessors => 1, + inline_constructor => 1, + inline_destructor => 0, + constructor_name => 'new', + constructor_class => 'Class::MOP::Method::Constructor', + debug => 0, + @args, + ); my $self = $class->_new( - 'metaclass' => $metaclass, - 'options' => $options, + 'metaclass' => delete $options{metaclass}, + 'options' => \%options, 'immutable_metaclass' => undef, 'inlined_constructor' => undef, ); @@ -52,188 +50,165 @@ sub _new { sub immutable_metaclass { my $self = shift; - $self->create_immutable_metaclass unless $self->{'immutable_metaclass'}; - - return $self->{'immutable_metaclass'}; + return $self->{'immutable_metaclass'} ||= $self->_create_immutable_metaclass; } sub metaclass { (shift)->{'metaclass'} } sub options { (shift)->{'options'} } sub inlined_constructor { (shift)->{'inlined_constructor'} } -sub create_immutable_metaclass { +sub _create_immutable_metaclass { my $self = shift; - # NOTE: - # The immutable version of the - # metaclass is just a anon-class - # which shadows the methods - # appropriately - $self->{'immutable_metaclass'} = Class::MOP::Class->create_anon_class( + # NOTE: The immutable version of the metaclass is just a + # anon-class which shadows the methods appropriately + return Class::MOP::Class->create_anon_class( superclasses => [ blessed($self->metaclass) ], - methods => $self->create_methods_for_immutable_metaclass, + methods => $self->_create_methods_for_immutable_metaclass, ); } - -my %DEFAULT_METHODS = ( - # I don't really understand this, but removing it breaks tests (groditi) - meta => sub { - my $self = shift; - # if it is not blessed, then someone is asking - # for the meta of Class::MOP::Immutable - return Class::MOP::Class->initialize($self) unless blessed($self); - # otherwise, they are asking for the metaclass - # which has been made immutable, which is itself - # except in the cases where it is a metaclass itself - # that has been made immutable and for that we need - # to dig a bit ... - if ($self->isa('Class::MOP::Class')) { - return $self->{'___original_class'}->meta; - } - else { - return $self; - } - }, - is_mutable => sub { 0 }, - is_immutable => sub { 1 }, - make_immutable => sub { () }, -); - -# NOTE: -# this will actually convert the -# existing metaclass to an immutable -# version of itself sub make_metaclass_immutable { - my ($self, $metaclass, $options) = @_; - - my %options = ( - inline_accessors => 1, - inline_constructor => 1, - inline_destructor => 0, - constructor_name => 'new', - debug => 0, - %$options, - ); + my $self = shift; - %$options = %options; # FIXME who the hell is relying on this?!? tests fail =( + $self->_inline_accessors; + $self->_inline_constructor; + $self->_inline_destructor; + $self->_check_memoized_methods; - $self->_inline_accessors( $metaclass, \%options ); - $self->_inline_constructor( $metaclass, \%options ); - $self->_inline_destructor( $metaclass, \%options ); - $self->_check_memoized_methods( $metaclass, \%options ); + my $metaclass = $self->metaclass; $metaclass->{'___original_class'} = blessed($metaclass); bless $metaclass => $self->immutable_metaclass->name; } sub _inline_accessors { - my ( $self, $metaclass, $options ) = @_; + my $self = shift; - return unless $options->{inline_accessors}; + return unless $self->options->{inline_accessors}; - foreach my $attr_name ( $metaclass->get_attribute_list ) { - $metaclass->get_attribute($attr_name)->install_accessors(1); + foreach my $attr_name ( $self->metaclass->get_attribute_list ) { + $self->metaclass->get_attribute($attr_name)->install_accessors(1); } } sub _inline_constructor { - my ( $self, $metaclass, $options ) = @_; + my $self = shift; - return unless $options->{inline_constructor}; + return unless $self->options->{inline_constructor}; return - unless $options->{replace_constructor} - or !$metaclass->has_method( $options->{constructor_name} ); + unless $self->options->{replace_constructor} + or !$self->metaclass->has_method( + $self->options->{constructor_name} + ); - my $constructor_class = $options->{constructor_class} - || 'Class::MOP::Method::Constructor'; + my $constructor_class = $self->options->{constructor_class}; my $constructor = $constructor_class->new( - options => $options, - metaclass => $metaclass, + options => $self->options, + metaclass => $self->metaclass, is_inline => 1, - package_name => $metaclass->name, - name => $options->{constructor_name}, + package_name => $self->metaclass->name, + name => $self->options->{constructor_name}, ); - if ( $options->{replace_constructor} or $constructor->can_be_inlined ) { - $metaclass->add_method( $options->{constructor_name} => $constructor ); + if ( $self->options->{replace_constructor} + or $constructor->can_be_inlined ) { + $self->metaclass->add_method( + $self->options->{constructor_name} => $constructor ); $self->{inlined_constructor} = $constructor; } } sub _inline_destructor { - my ( $self, $metaclass, $options ) = @_; + my $self = shift; - return unless $options->{inline_destructor}; + return unless $self->options->{inline_destructor}; - ( exists $options->{destructor_class} ) + ( exists $self->options->{destructor_class} ) || confess "The 'inline_destructor' option is present, but " . "no destructor class was specified"; - my $destructor_class = $options->{destructor_class}; + my $destructor_class = $self->options->{destructor_class}; - return unless $destructor_class->is_needed($metaclass); + return unless $destructor_class->is_needed( $self->metaclass ); my $destructor = $destructor_class->new( - options => $options, - metaclass => $metaclass, - package_name => $metaclass->name, + options => $self->options, + metaclass => $self->metaclass, + package_name => $self->metaclass->name, name => 'DESTROY' ); - return unless $destructor->is_needed; - - $metaclass->add_method( 'DESTROY' => $destructor ) + $self->metaclass->add_method( 'DESTROY' => $destructor ); } sub _check_memoized_methods { - my ( $self, $metaclass, $options ) = @_; + my $self = shift; my $memoized_methods = $self->options->{memoize}; foreach my $method_name ( keys %{$memoized_methods} ) { my $type = $memoized_methods->{$method_name}; - ( $metaclass->can($method_name) ) + ( $self->metaclass->can($method_name) ) || confess "Could not find the method '$method_name' in " - . $metaclass->name; + . $self->metaclass->name; } } +my %DEFAULT_METHODS = ( + # I don't really understand this, but removing it breaks tests (groditi) + meta => sub { + my $self = shift; + # if it is not blessed, then someone is asking + # for the meta of Class::MOP::Immutable + return Class::MOP::Class->initialize($self) unless blessed($self); + # otherwise, they are asking for the metaclass + # which has been made immutable, which is itself + # except in the cases where it is a metaclass itself + # that has been made immutable and for that we need + # to dig a bit ... + if ($self->isa('Class::MOP::Class')) { + return Class::MOP::class_of($self->{'___original_class'}); + } + else { + return $self; + } + }, + is_mutable => sub { 0 }, + is_immutable => sub { 1 }, + make_immutable => sub { () }, +); -sub create_methods_for_immutable_metaclass { +sub _create_methods_for_immutable_metaclass { my $self = shift; - 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}; + my $meta = Class::MOP::class_of($metaclass); 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 ), + $self->_make_read_only_methods, + $self->_make_uncallable_methods, + $self->_make_memoized_methods, + $self->_make_wrapped_methods, get_mutable_metaclass_name => sub { (shift)->{'___original_class'} }, immutable_transformer => sub {$self}, }; } sub _make_read_only_methods { - my ( $self, $metaclass, $meta ) = @_; + my $self = shift; + + my $metameta = Class::MOP::class_of($self->metaclass); my %methods; foreach my $read_only_method ( @{ $self->options->{read_only} } ) { - my $method = $meta->find_method_by_name($read_only_method); + my $method = $metameta->find_method_by_name($read_only_method); ( defined $method ) || confess "Could not find the method '$read_only_method' in " - . $metaclass->name; + . $self->metaclass->name; $methods{$read_only_method} = sub { confess "This method is read-only" if scalar @_ > 1; @@ -245,7 +220,7 @@ sub _make_read_only_methods { } sub _make_uncallable_methods { - my ( $self, $metaclass, $meta ) = @_; + my $self = shift; my %methods; foreach my $cannot_call_method ( @{ $self->options->{cannot_call} } ) { @@ -259,15 +234,17 @@ sub _make_uncallable_methods { } sub _make_memoized_methods { - my ( $self, $metaclass, $meta ) = @_; + my $self = shift; my %methods; + my $metameta = Class::MOP::class_of($self->metaclass); + 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); + my $method = $metameta->find_method_by_name($method_name); if ( $type eq 'ARRAY' ) { $methods{$method_name} = sub { @@ -296,18 +273,20 @@ sub _make_memoized_methods { } sub _make_wrapped_methods { - my ( $self, $metaclass, $meta ) = @_; + my $self = shift; my %methods; my $wrapped_methods = $self->options->{wrapped}; + my $metameta = Class::MOP::class_of($self->metaclass); + foreach my $method_name ( keys %{$wrapped_methods} ) { - my $method = $meta->find_method_by_name($method_name); + my $method = $metameta->find_method_by_name($method_name); ( defined $method ) || confess "Could not find the method '$method_name' in " - . $metaclass->name; + . $self->metaclass->name; my $wrapper = $wrapped_methods->{$method_name}; @@ -318,28 +297,31 @@ sub _make_wrapped_methods { } sub make_metaclass_mutable { - my ($self, $immutable, $options) = @_; + my $self = shift; - my %options = %$options; + my $metaclass = $self->metaclass; - my $original_class = $immutable->get_mutable_metaclass_name; - delete $immutable->{'___original_class'} ; - bless $immutable => $original_class; + my $original_class = $metaclass->get_mutable_metaclass_name; + delete $metaclass->{'___original_class'}; + bless $metaclass => $original_class; 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}; - ($immutable->can($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}; + ( $metaclass->can($method_name) ) + || confess "Could not find the method '$method_name' in " + . $metaclass->name; + if ( $type eq 'SCALAR' || $type eq 'ARRAY' || $type eq 'HASH' ) { + delete $metaclass->{ '___' . $method_name }; } } - if ($options{inline_destructor} && $immutable->has_method('DESTROY')) { - $immutable->remove_method('DESTROY') - if blessed($immutable->get_method('DESTROY')) eq $options{destructor_class}; + if ( $self->options->{inline_destructor} + && $metaclass->has_method('DESTROY') ) { + $metaclass->remove_method('DESTROY') + if blessed( $metaclass->get_method('DESTROY') ) eq + $self->options->{destructor_class}; } # NOTE: @@ -359,11 +341,17 @@ sub make_metaclass_mutable { # 14:26 <@stevan> the only user of ::Method::Constructor is immutable # 14:27 <@stevan> if someone uses it outside of immutable,.. they are either: mst or groditi # 14:27 <@stevan> so I am not worried - if ($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} ); + if ( $self->options->{inline_constructor} + && $metaclass->has_method( $self->options->{constructor_name} ) ) { + my $constructor_class = $self->options->{constructor_class} + || 'Class::MOP::Method::Constructor'; + + if ( + blessed( + $metaclass->get_method( $self->options->{constructor_name} ) + ) eq $constructor_class + ) { + $metaclass->remove_method( $self->options->{constructor_name} ); $self->{inlined_constructor} = undef; } } @@ -402,71 +390,124 @@ Class::MOP::Immutable - A class to transform Class::MOP::Class metaclasses } }); - $immutable_metaclass->make_metaclass_immutable(@_) + $immutable_metaclass->make_metaclass_immutable; =head1 DESCRIPTION -This is basically a module for applying a transformation on a given -metaclass. Current features include making methods read-only, -making methods un-callable and memoizing methods (in a type specific -way too). +This class encapsulates the logic behind immutabilization. + +This class provides generic immutabilization logic. Decisions about +I gets transformed are up to the caller. -This module is not for the feint of heart, it does some whacky things -to the metaclass in order to make it immutable. If you are just curious, -I suggest you turn back now, there is nothing to see here. +Immutabilization allows for a number of transformations. It can ask +the calling metaclass to inline methods such as the constructor, +destructor, or accessors. It can memoize metaclass accessors +themselves. It can also turn read-write accessors in the metaclass +into read-only methods, and make attempting to set these values an +error. Finally, it can make some methods throw an exception when they +are called. This is used to disable methods that can alter the class. =head1 METHODS =over 4 -=item B +=item B<< Class::MOP::Immutable->new($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<$metaclass> using the C -method. +This method takes a metaclass object (typically a L +object) and a hash of options. -=item B +It returns a new transformer, but does not actually do any +transforming yet. -Returns the options HASH set in C. +This method accepts the following options: -=item B +=over 8 -Returns the metaclass set in C. +=item * inline_accessors -=item B +=item * inline_constructor -Returns the immutable metaclass created within C. +=item * inline_destructor -=back +These are all booleans indicating whether the specified method(s) +should be inlined. -=over 4 +By default, accessors and the constructor are inlined, but not the +destructor. + +=item * replace_constructor + +This is a boolean indicating whether an existing constructor should be +replaced when inlining a constructor. This defaults to false. + +=item * constructor_name + +This is the constructor method name. This defaults to "new". + +=item * constructor_class + +The name of the method metaclass for constructors. It will be used to +generate the inlined constructor. This defaults to +"Class::MOP::Method::Constructor". -=item B +=item * destructor_class -This will create the immutable version of the C<$metaclass>, but will -not actually change the original metaclass. +The name of the method metaclass for destructors. It will be used to +generate the inlined destructor. This defaults to +"Class::MOP::Method::Denstructor". -=item B +=item * memoize -This will create all the methods for the immutable metaclass based -on the C<%options> passed into C. +This option takes a hash reference. They keys are method names to be +memoized, and the values are the type of data the method returns. This +can be one of "SCALAR", "ARRAY", or "HASH". -=item B +=item * read_only -This will actually change the C<$metaclass> into the immutable version. +This option takes an array reference of read-write methods which will +be made read-only. After they are transformed, attempting to set them +will throw an error. -=item B +=item * cannot_call -This will change the C<$metaclass> into the mutable version by reversing -the immutable process. C<%options> should be the same options that were -given to make_metaclass_immutable. +This option takes an array reference of methods which cannot be called +after immutabilization. Attempting to call these methods will throw an +error. -=item B +=item * wrapped + +This option takes a hash reference. The keys are method names and the +body is a subroutine reference which will wrap the named method. This +allows you to do some sort of custom transformation to a method. + +=back + +=item B<< $transformer->options >> + +Returns a hash reference of the options passed to C. + +=item B<< $transformer->metaclass >> + +Returns the metaclass object passed to C. + +=item B<< $transformer->immutable_metaclass >> + +Returns the immutable metaclass object that is created by the +transformation process. + +=item B<< $transformer->inlined_constructor >> If the constructor was inlined, this returns the constructor method object that was created to do this. +=item B<< $transformer->make_metaclass_immutable >> + +Makes the transformer's metaclass immutable. + +=item B<< $transformer->make_metaclass_mutable >> + +Makes the transformer's metaclass mutable. + =back =head1 AUTHORS @@ -475,7 +516,7 @@ Stevan Little Estevan@iinteractive.comE =head1 COPYRIGHT AND LICENSE -Copyright 2006-2008 by Infinity Interactive, Inc. +Copyright 2006-2009 by Infinity Interactive, Inc. L