X-Git-Url: http://git.shadowcat.co.uk/gitweb/gitweb.cgi?p=gitmo%2FMouse.git;a=blobdiff_plain;f=lib%2FMouse%2FMeta%2FAttribute.pm;h=c5482aa0425eef92d7a1c35d6498ceb4b7470687;hp=ec752cb08aa0fc5b6ad5d2df7b4edebdadb281b8;hb=b06ce1f502945c13a52c503f1a651fe92c91c773;hpb=53875581c2449e237cc1135b8c2cf1674a874aed diff --git a/lib/Mouse/Meta/Attribute.pm b/lib/Mouse/Meta/Attribute.pm index ec752cb..c5482aa 100644 --- a/lib/Mouse/Meta/Attribute.pm +++ b/lib/Mouse/Meta/Attribute.pm @@ -1,18 +1,21 @@ package Mouse::Meta::Attribute; -use strict; -use warnings; +use Mouse::Util qw(:meta); # enables strict and warnings use Carp (); -use Scalar::Util qw(weaken); - -use Mouse::Util qw(:meta); use Mouse::Meta::TypeConstraint; use Mouse::Meta::Method::Accessor; + sub _process_options{ my($class, $name, $args) = @_; + + # XXX: for backward compatibility (with method modifiers) + if($class->can('canonicalize_args') != \&canonicalize_args){ + %{$args} = $class->canonicalize_args($name, %{$args}); + } + # taken from Class::MOP::Attribute::new defined($name) @@ -26,8 +29,12 @@ sub _process_options{ my $can_be_required = defined( $args->{init_arg} ); if(exists $args->{builder}){ + # XXX: + # Moose refuses a CODE ref builder, but Mouse doesn't for backward compatibility + # This feature will be changed in a future. (gfx) $class->throw_error('builder must be a defined scalar value which is a method name') - if ref $args->{builder} || !(defined $args->{builder}); + #if ref $args->{builder} || !defined $args->{builder}; + if !defined $args->{builder}; $can_be_required++; } @@ -119,10 +126,6 @@ sub _process_options{ || $class->throw_error("You cannot have lazy attribute ($name) without specifying a default value for it"); } - # XXX: for backward compatibility (with method modifiers) - if($class->can('canonicalize_args') != \&canonicalize_args){ - %{$args} = $class->canonicalize_args($name, %{$args}); - } return; } @@ -136,11 +139,11 @@ sub new { $args{name} = $name; - my $instance = bless \%args, $class; + my $self = bless \%args, $class; # extra attributes if($class ne __PACKAGE__){ - $class->meta->_initialize_instance($instance,\%args); + $class->meta->_initialize_object($self, \%args); } # XXX: there is no fast way to check attribute validity @@ -150,64 +153,19 @@ sub new { # Carp::cluck("Found unknown argument(s) passed to '$name' attribute constructor in '$class': @bad"); # } - return $instance + return $self; } -# readers - -sub name { $_[0]->{name} } -sub associated_class { $_[0]->{associated_class} } - -sub accessor { $_[0]->{accessor} } -sub reader { $_[0]->{reader} } -sub writer { $_[0]->{writer} } -sub predicate { $_[0]->{predicate} } -sub clearer { $_[0]->{clearer} } -sub handles { $_[0]->{handles} } - -sub _is_metadata { $_[0]->{is} } -sub is_required { $_[0]->{required} } -sub default { $_[0]->{default} } -sub is_lazy { $_[0]->{lazy} } -sub is_lazy_build { $_[0]->{lazy_build} } -sub is_weak_ref { $_[0]->{weak_ref} } -sub init_arg { $_[0]->{init_arg} } -sub type_constraint { $_[0]->{type_constraint} } - -sub trigger { $_[0]->{trigger} } -sub builder { $_[0]->{builder} } -sub should_auto_deref { $_[0]->{auto_deref} } -sub should_coerce { $_[0]->{coerce} } - -sub get_read_method { $_[0]->{reader} || $_[0]->{accessor} } -sub get_write_method { $_[0]->{writer} || $_[0]->{accessor} } - -# predicates - -sub has_accessor { exists $_[0]->{accessor} } -sub has_reader { exists $_[0]->{reader} } -sub has_writer { exists $_[0]->{writer} } -sub has_predicate { exists $_[0]->{predicate} } -sub has_clearer { exists $_[0]->{clearer} } -sub has_handles { exists $_[0]->{handles} } - -sub has_default { exists $_[0]->{default} } -sub has_type_constraint { exists $_[0]->{type_constraint} } -sub has_trigger { exists $_[0]->{trigger} } -sub has_builder { exists $_[0]->{builder} } - -sub has_read_method { exists $_[0]->{reader} || exists $_[0]->{accessor} } -sub has_write_method { exists $_[0]->{writer} || exists $_[0]->{accessor} } - -sub _create_args { +sub has_read_method { $_[0]->has_reader || $_[0]->has_accessor } +sub has_write_method { $_[0]->has_writer || $_[0]->has_accessor } + +sub _create_args { # DEPRECATED $_[0]->{_create_args} = $_[1] if @_ > 1; $_[0]->{_create_args} } -sub accessor_metaclass { 'Mouse::Meta::Method::Accessor' } - sub interpolate_class{ - my($class, $name, $args) = @_; + my($class, $args) = @_; if(my $metaclass = delete $args->{metaclass}){ $class = Mouse::Util::resolve_metaclass_alias( Attribute => $metaclass ); @@ -240,83 +198,90 @@ sub interpolate_class{ return( $class, @traits ); } -sub canonicalize_args{ +sub canonicalize_args{ # DEPRECATED my ($self, $name, %args) = @_; Carp::cluck("$self->canonicalize_args has been deprecated." - . "Use \$self->_process_options instead."); + . "Use \$self->_process_options instead.") + if _MOUSE_VERBOSE; return %args; } -sub create { +sub create { # DEPRECATED my ($self, $class, $name, %args) = @_; Carp::cluck("$self->create has been deprecated." - . "Use \$meta->add_attribute and \$attr->install_accessors instead."); + . "Use \$meta->add_attribute and \$attr->install_accessors instead.") + if _MOUSE_VERBOSE; # noop return $self; } +sub _coerce_and_verify { + my($self, $value, $instance) = @_; + + my $type_constraint = $self->{type_constraint}; + return $value if !defined $type_constraint; + + if ($self->should_coerce && $type_constraint->has_coercion) { + $value = $type_constraint->coerce($value); + } + + $self->verify_against_type_constraint($value); + + return $value; +} + sub verify_against_type_constraint { my ($self, $value) = @_; - my $tc = $self->type_constraint; - return 1 unless $tc; - local $_ = $value; - return 1 if $tc->check($value); + my $type_constraint = $self->{type_constraint}; + return 1 if !$type_constraint; + return 1 if $type_constraint->check($value); - $self->verify_type_constraint_error($self->name, $value, $tc); + $self->verify_type_constraint_error($self->name, $value, $type_constraint); } sub verify_type_constraint_error { my($self, $name, $value, $type) = @_; - $self->throw_error("Attribute ($name) does not pass the type constraint because: " . $type->get_message($value)); + $self->throw_error("Attribute ($name) does not pass the type constraint because: " + . $type->get_message($value)); } -sub coerce_constraint { ## my($self, $value) = @_; +sub coerce_constraint { # DEPRECATED my $type = $_[0]->{type_constraint} or return $_[1]; - return Mouse::Util::TypeConstraints->typecast_constraints($_[0]->associated_class->name, $_[0]->type_constraint, $_[1]); -} -sub _canonicalize_handles { - my $self = shift; - my $handles = shift; + Carp::cluck("coerce_constraint() has been deprecated, which was an internal utility anyway"); - if (ref($handles) eq 'HASH') { - return %$handles; - } - elsif (ref($handles) eq 'ARRAY') { - return map { $_ => $_ } @$handles; - } - else { - $self->throw_error("Unable to canonicalize the 'handles' option with $handles"); - } + return Mouse::Util::TypeConstraints->typecast_constraints($_[0]->associated_class->name, $type, $_[1]); } sub clone_and_inherit_options{ - my $self = shift; - my $name = shift; + my($self, %args) = @_; + + my($attribute_class, @traits) = ref($self)->interpolate_class(\%args); - return ref($self)->new($name, %{$self}, @_ == 1 ? %{$_[0]} : @_); + $args{traits} = \@traits if @traits; + return $attribute_class->new($self->name, %{$self}, %args); } -sub clone_parent { +sub clone_parent { # DEPRECATED my $self = shift; my $class = shift; my $name = shift; my %args = ($self->get_parent_args($class, $name), @_); Carp::cluck("$self->clone_parent has been deprecated." - . "Use \$meta->add_attribute and \$attr->install_accessors instead."); + . "Use \$meta->add_attribute and \$attr->install_accessors instead.") + if _MOUSE_VERBOSE; - - $self->create($class, $name, %args); + $self->clone_and_inherited_args($class, $name, %args); } -sub get_parent_args { +sub get_parent_args { # DEPRECATED my $self = shift; my $class = shift; my $name = shift; @@ -330,21 +295,109 @@ sub get_parent_args { $self->throw_error("Could not find an attribute by the name of '$name' to inherit from"); } + +sub get_read_method { + $_[0]->reader || $_[0]->accessor +} +sub get_write_method { + $_[0]->writer || $_[0]->accessor +} + +sub get_read_method_ref{ + my($self) = @_; + + $self->{_read_method_ref} ||= do{ + my $metaclass = $self->associated_class + or $self->throw_error('No asocciated class for ' . $self->name); + + my $reader = $self->{reader} || $self->{accessor}; + if($reader){ + $metaclass->name->can($reader); + } + else{ + $self->accessor_metaclass->_generate_reader($self, $metaclass); + } + }; +} + +sub get_write_method_ref{ + my($self) = @_; + + $self->{_write_method_ref} ||= do{ + my $metaclass = $self->associated_class + or $self->throw_error('No asocciated class for ' . $self->name); + + my $reader = $self->{writer} || $self->{accessor}; + if($reader){ + $metaclass->name->can($reader); + } + else{ + $self->accessor_metaclass->_generate_writer($self, $metaclass); + } + }; +} + +sub _canonicalize_handles { + my($self, $handles) = @_; + + if (ref($handles) eq 'HASH') { + return %$handles; + } + elsif (ref($handles) eq 'ARRAY') { + return map { $_ => $_ } @$handles; + } + elsif (ref($handles) eq 'Regexp') { + my $class_or_role = ($self->{isa} || $self->{does}) + || $self->throw_error("Cannot delegate methods based on a Regexp without a type constraint (isa)"); + + my $meta = Mouse::Meta::Class->initialize("$class_or_role"); # "" for stringify + return map { $_ => $_ } + grep { $_ ne 'meta' && !Mouse::Object->can($_) && $_ =~ $handles } + $meta->isa('Mouse::Meta::Class') ? $meta->get_all_method_names : $meta->get_method_list; + } + else { + $self->throw_error("Unable to canonicalize the 'handles' option with $handles"); + } +} + +sub associate_method{ + my ($attribute, $method) = @_; + $attribute->{associated_methods}++; + return; +} + sub install_accessors{ my($attribute) = @_; - my $metaclass = $attribute->{associated_class}; - my $generator_class = $attribute->accessor_metaclass; + my $metaclass = $attribute->associated_class; + my $accessor_class = $attribute->accessor_metaclass; - foreach my $type(qw(accessor reader writer predicate clearer handles)){ + foreach my $type(qw(accessor reader writer predicate clearer)){ if(exists $attribute->{$type}){ - my $installer = '_install_' . $type; - $generator_class->$installer($attribute, $attribute->{$type}, $metaclass); - $attribute->{associated_methods}++; + my $generator = '_generate_' . $type; + my $code = $accessor_class->$generator($attribute, $metaclass); + $metaclass->add_method($attribute->{$type} => $code); + $attribute->associate_method($code); + } + } + + # install delegation + if(exists $attribute->{handles}){ + my %handles = $attribute->_canonicalize_handles($attribute->{handles}); + my $reader = $attribute->get_read_method_ref; + + while(my($handle_name, $method_to_call) = each %handles){ + my $code = $accessor_class->_generate_delegation($attribute, $metaclass, + $reader, $handle_name, $method_to_call); + + $metaclass->add_method($handle_name => $code); + $attribute->associate_method($code); } } + if($attribute->can('create') != \&create){ + # backword compatibility $attribute->create($metaclass, $attribute->name, %{$attribute}); } @@ -364,89 +417,149 @@ __END__ =head1 NAME -Mouse::Meta::Attribute - attribute metaclass +Mouse::Meta::Attribute - The Mouse attribute metaclass + +=head1 VERSION + +This document describes Mouse version 0.40_01 =head1 METHODS -=head2 new %args -> Mouse::Meta::Attribute +=head2 C<< new(%options) -> Mouse::Meta::Attribute >> Instantiates a new Mouse::Meta::Attribute. Does nothing else. -=head2 create OwnerClass, AttributeName, %args -> Mouse::Meta::Attribute +It adds the following options to the constructor: -Creates a new attribute in OwnerClass. Accessors and helper methods are -installed. Some error checking is done. +=over 4 -=head2 name -> AttributeName +=item C<< is => 'ro', 'rw', 'bare' >> -=head2 associated_class -> OwnerClass +This provides a shorthand for specifying the C, C, or +C names. If the attribute is read-only ('ro') then it will +have a C method with the same attribute as the name. -=head2 is_required -> Bool +If it is read-write ('rw') then it will have an C method +with the same name. If you provide an explicit C for a +read-write attribute, then you will have a C with the same +name as the attribute, and a C with the name you provided. -=head2 default -> Item +Use 'bare' when you are deliberately not installing any methods +(accessor, reader, etc.) associated with this attribute; otherwise, +Moose will issue a deprecation warning when this attribute is added to a +metaclass. -=head2 has_default -> Bool +=item C<< isa => Type >> -=head2 is_lazy -> Bool +This option accepts a type. The type can be a string, which should be +a type name. If the type name is unknown, it is assumed to be a class +name. -=head2 predicate -> MethodName | Undef +This option can also accept a L object. -=head2 has_predicate -> Bool +If you I provide a C option, then your C option must +be a class name, and that class must do the role specified with +C. -=head2 clearer -> MethodName | Undef +=item C<< does => Role >> -=head2 has_clearer -> Bool +This is short-hand for saying that the attribute's type must be an +object which does the named role. -=head2 handles -> { LocalName => RemoteName } +B -=head2 has_handles -> Bool +=item C<< coerce => Bool >> -=head2 is_weak_ref -> Bool +This option is only valid for objects with a type constraint +(C). If this is true, then coercions will be applied whenever +this attribute is set. -=head2 init_arg -> Str +You can make both this and the C option true. -=head2 type_constraint -> Str +=item C<< trigger => CodeRef >> -=head2 has_type_constraint -> Bool +This option accepts a subroutine reference, which will be called after +the attribute is set. -=head2 trigger => CODE | Undef +=item C<< required => Bool >> -=head2 has_trigger -> Bool +An attribute which is required must be provided to the constructor. An +attribute which is required can also have a C or C, +which will satisfy its required-ness. -=head2 builder => MethodName | Undef +A required attribute must have a C, C or a +non-C C -=head2 has_builder -> Bool +=item C<< lazy => Bool >> -=head2 is_lazy_build => Bool +A lazy attribute must have a C or C. When an +attribute is lazy, the default value will not be calculated until the +attribute is read. -=head2 should_auto_deref -> Bool +=item C<< weak_ref => Bool >> -Informational methods. +If this is true, the attribute's value will be stored as a weak +reference. -=head2 verify_against_type_constraint Item -> 1 | ERROR +=item C<< auto_deref => Bool >> -Checks that the given value passes this attribute's type constraint. Returns 1 -on success, otherwise Ces. +If this is true, then the reader will dereference the value when it is +called. The attribute must have a type constraint which defines the +attribute as an array or hash reference. + +=item C<< lazy_build => Bool >> -=head2 canonicalize_args Name, %args -> %args +Setting this to true makes the attribute lazy and provides a number of +default methods. -Canonicalizes some arguments to create. In particular, C is -canonicalized into C, C, etc. + has 'size' => ( + is => 'ro', + lazy_build => 1, + ); -=head2 validate_args Name, \%args -> 1 | ERROR +is equivalent to this: -Checks that the arguments to create the attribute (ie those specified by -C) are valid. + has 'size' => ( + is => 'ro', + lazy => 1, + builder => '_build_size', + clearer => 'clear_size', + predicate => 'has_size', + ); -=head2 clone_parent OwnerClass, AttributeName, %args -> Mouse::Meta::Attribute +=back -Creates a new attribute in OwnerClass, inheriting options from parent classes. +=head2 C<< associate_method(Method) >> + +Associates a method with the attribute. Typically, this is called internally +when an attribute generates its accessors. + +Currently the argument I is ignored in Mouse. + +=head2 C<< verify_against_type_constraint(Item) -> TRUE | ERROR >> + +Checks that the given value passes this attribute's type constraint. Returns C +on success, otherwise Ces. + +=head2 C<< clone_and_inherit_options(options) -> Mouse::Meta::Attribute >> + +Creates a new attribute in the owner class, inheriting options from parent classes. Accessors and helper methods are installed. Some error checking is done. -=head2 get_parent_args OwnerClass, AttributeName -> Hash +=head2 C<< get_read_method_ref >> + +=head2 C<< get_write_method_ref >> + +Returns the subroutine reference of a method suitable for reading or +writing the attribute's value in the associated class. These methods +always return a subroutine reference, regardless of whether or not the +attribute is read- or write-only. + +=head1 SEE ALSO + +L -Returns the options that the parent class of C used for attribute -C. +L =cut