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=a4827e866074b05aa4a8ef6a2d49f8462133f3d4;hp=dec1a54e89b8d426a5f69000316ea480762d4f66;hb=f7e41edaceee0d549a2d664378cfcf85dcf9454b;hpb=2efc0af104c1926c066f50e1785236254bda12a2 diff --git a/lib/Mouse/Meta/Attribute.pm b/lib/Mouse/Meta/Attribute.pm index dec1a54..a4827e8 100644 --- a/lib/Mouse/Meta/Attribute.pm +++ b/lib/Mouse/Meta/Attribute.pm @@ -1,83 +1,71 @@ 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; use Mouse::Meta::TypeConstraint; -use Mouse::Meta::Method::Accessor; - -#my %valid_attrs = map{ $_ => undef } qw( -# name -# reader writer accessor clearer predicate -# builder init_arg default initializer definition_context -# -# is -# isa does -# required -# lazy -# lazy_build -# coerce -# weak_ref -# auto_deref -# type_constraint -# trigger -# handles -# documentation -# traits -#); -sub new { - my ($class, $name, %options) = @_; +#use Mouse::Meta::Method::Accessor; +use Mouse::Meta::Method::Delegation; + + +sub _process_options{ + my($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) or $class->throw_error('You must provide a name for the attribute'); - $options{name} = $name; - if(!exists $options{init_arg}){ - $options{init_arg} = $name; + if(!exists $args->{init_arg}){ + $args->{init_arg} = $name; } # 'required' requires eigher 'init_arg', 'builder', or 'default' - my $can_be_required = defined( $options{init_arg} ); + my $can_be_required = defined( $args->{init_arg} ); - if(exists $options{builder}){ - $class->throw_error('builder must be a defined scalar value which is a method name') - if ref $options{builder} || !(defined $options{builder}); + 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 !defined $args->{builder}; $can_be_required++; } - elsif(exists $options{default}){ - if(ref $options{default} && ref($options{default}) ne 'CODE'){ + elsif(exists $args->{default}){ + if(ref $args->{default} && ref($args->{default}) ne 'CODE'){ $class->throw_error("References are not allowed as default values, you must " . "wrap the default of '$name' in a CODE reference (ex: sub { [] } and not [])"); } $can_be_required++; } - if( $options{required} && !$can_be_required ) { - $class->throw_error("You cannot have a required attribute ($name) without a default, builder, or an init_arg"); + if( $args->{required} && !$can_be_required ) { + $class->throw_error("You cannot have a required attribute ($name) without a default, builder, or an init_arg"); } - # taken from Mouse::Meta::Attribute->new and _process_options + # taken from Mouse::Meta::Attribute->new and _process_args-> - if(exists $options{is}){ - my $is = $options{is}; + if(exists $args->{is}){ + my $is = $args->{is}; if($is eq 'ro'){ - $options{reader} ||= $name; + $args->{reader} ||= $name; } elsif($is eq 'rw'){ - if(exists $options{writer}){ - $options{reader} ||= $name; + if(exists $args->{writer}){ + $args->{reader} ||= $name; } else{ - $options{accessor} ||= $name; + $args->{accessor} ||= $name; } } elsif($is eq 'bare'){ @@ -90,216 +78,218 @@ sub new { } my $tc; - if(exists $options{isa}){ - $options{type_constraint} = Mouse::Util::TypeConstraints::find_or_create_isa_type_constraint($options{isa}); + if(exists $args->{isa}){ + $args->{type_constraint} = Mouse::Util::TypeConstraints::find_or_create_isa_type_constraint($args->{isa}); } - elsif(exists $options{does}){ - $options{type_constraint} = Mouse::Util::TypeConstraints::find_or_create_does_type_constraint($options{does}); + elsif(exists $args->{does}){ + $args->{type_constraint} = Mouse::Util::TypeConstraints::find_or_create_does_type_constraint($args->{does}); } - $tc = $options{type_constraint}; + $tc = $args->{type_constraint}; - if($options{coerce}){ + if($args->{coerce}){ defined($tc) || $class->throw_error("You cannot have coercion without specifying a type constraint on attribute ($name)"); - $options{weak_ref} - && $class->throw_error("You cannot have a weak reference to a coerced value on attribute ($name)"); + $args->{weak_ref} + && $class->throw_error("You cannot have a weak reference to a coerced value on attribute ($name)"); } - if ($options{lazy_build}) { - exists($options{default}) - && $class->throw_error("You can not use lazy_build and default for the same attribute ($name)"); - - $options{lazy} = 1; - $options{builder} ||= "_build_${name}"; - if ($name =~ /^_/) { - $options{clearer} ||= "_clear${name}"; - $options{predicate} ||= "_has${name}"; - } - else { - $options{clearer} ||= "clear_${name}"; - $options{predicate} ||= "has_${name}"; - } + if ($args->{lazy_build}) { + exists($args->{default}) + && $class->throw_error("You can not use lazy_build and default for the same attribute ($name)"); + + $args->{lazy} = 1; + $args->{builder} ||= "_build_${name}"; + if ($name =~ /^_/) { + $args->{clearer} ||= "_clear${name}"; + $args->{predicate} ||= "_has${name}"; + } + else { + $args->{clearer} ||= "clear_${name}"; + $args->{predicate} ||= "has_${name}"; + } } - if ($options{auto_deref}) { - defined($tc) - || $class->throw_error("You cannot auto-dereference without specifying a type constraint on attribute ($name)"); + if ($args->{auto_deref}) { + defined($tc) + || $class->throw_error("You cannot auto-dereference without specifying a type constraint on attribute ($name)"); - ( $tc->is_a_type_of('ArrayRef') || $tc->is_a_type_of('HashRef') ) - || $class->throw_error("You cannot auto-dereference anything other than a ArrayRef or HashRef on attribute ($name)"); + ( $tc->is_a_type_of('ArrayRef') || $tc->is_a_type_of('HashRef') ) + || $class->throw_error("You cannot auto-dereference anything other than a ArrayRef or HashRef on attribute ($name)"); } - if (exists $options{trigger}) { - ('CODE' eq ref $options{trigger}) - || $class->throw_error("Trigger must be a CODE ref on attribute ($name)"); + if (exists $args->{trigger}) { + ('CODE' eq ref $args->{trigger}) + || $class->throw_error("Trigger must be a CODE ref on attribute ($name)"); } - if ($options{lazy}) { - (exists $options{default} || defined $options{builder}) - || $class->throw_error("You cannot have lazy attribute ($name) without specifying a default value for it"); + if ($args->{lazy}) { + (exists $args->{default} || defined $args->{builder}) + || $class->throw_error("You cannot have lazy attribute ($name) without specifying a default value for it"); } - if(my $metaclass = delete $options{metaclass}){ - $class = Mouse::Util::resolve_metaclass_alias( Attribute => $metaclass ); - } + return; +} - if(my $traits_ref = delete $options{traits}){ - my @traits; - for (my $i = 9; $i < @{$traits_ref}; $i++) { - my $trait = Mouse::Util::resolve_metaclass_alias(Attribute => $traits_ref->[$i], trait => 1); - - next if $class->does($trait); - - push @traits, $trait; - - # are there options? - push @traits, $traits_ref->[++$i] - if ref($traits_ref->[$i+1]); - } +sub new { + my $class = shift; + my $name = shift; - if (@traits) { - $class = Mouse::Meta::Class->create_anon_class( - superclasses => [ $class ], - roles => [ @traits ], - cache => 1, - )->name; - } + my %args = (@_ == 1) ? %{ $_[0] } : @_; + + $class->_process_options($name, \%args); + + $args{name} = $name; + + my $self = bless \%args, $class; + + # extra attributes + if($class ne __PACKAGE__){ + $class->meta->_initialize_object($self, \%args); } # XXX: there is no fast way to check attribute validity -# my @bad = grep{ !exists $valid_attrs{$_} } keys %options; +# my @bad = ...; # if(@bad){ # @bad = sort @bad; # Carp::cluck("Found unknown argument(s) passed to '$name' attribute constructor in '$class': @bad"); # } - return bless \%options, $class; + 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} } - -# 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 _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, $args) = @_; -sub create { - my ($self, $class, $name, %args) = @_; + if(my $metaclass = delete $args->{metaclass}){ + $class = Mouse::Util::resolve_metaclass_alias( Attribute => $metaclass ); + } - my $attribute = $self->new($name, %args); + my @traits; + if(my $traits_ref = delete $args->{traits}){ - $attribute->_create_args(\%args); + for (my $i = 0; $i < @{$traits_ref}; $i++) { + my $trait = Mouse::Util::resolve_metaclass_alias(Attribute => $traits_ref->[$i], trait => 1); - $class->add_attribute($attribute); - weaken($attribute->{associated_class} = $class); + next if $class->does($trait); - my $associated_methods = 0; + push @traits, $trait; - my $generator_class = $self->accessor_metaclass; - foreach my $type(qw(accessor reader writer predicate clearer handles)){ - if(exists $attribute->{$type}){ - my $installer = '_install_' . $type; - $generator_class->$installer($attribute, $attribute->{$type}, $class); - $associated_methods++; + # are there options? + push @traits, $traits_ref->[++$i] + if ref($traits_ref->[$i+1]); + } + + if (@traits) { + $class = Mouse::Meta::Class->create_anon_class( + superclasses => [ $class ], + roles => \@traits, + cache => 1, + )->name; } } - if($associated_methods == 0 && ($attribute->_is_metadata || '') ne 'bare'){ - Carp::cluck(qq{Attribute ($name) of class }.$class->name.qq{ has no associated methods (did you mean to provide an "is" argument?)}); + return( $class, @traits ); +} + +sub canonicalize_args{ # DEPRECATED + my ($self, $name, %args) = @_; + + Carp::cluck("$self->canonicalize_args has been deprecated." + . "Use \$self->_process_options instead.") + if Mouse::Util::_MOUSE_VERBOSE; + + return %args; +} + +sub create { # DEPRECATED + my ($self, $class, $name, %args) = @_; + + Carp::cluck("$self->create has been deprecated." + . "Use \$meta->add_attribute and \$attr->install_accessors instead.") + if Mouse::Util::_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); } - return $attribute; + $self->verify_against_type_constraint($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, $_[1]); + + Carp::cluck("coerce_constraint() has been deprecated, which was an internal utility anyway"); + + return Mouse::Util::TypeConstraints->typecast_constraints($_[0]->associated_class->name, $type, $_[1]); } -sub _canonicalize_handles { - my $self = shift; - my $handles = shift; +sub clone_and_inherit_options{ + my($self, %args) = @_; - 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 $handles"); + my($attribute_class, @traits) = ref($self)->interpolate_class(\%args); + + $args{traits} = \@traits if @traits; + # do not inherit the 'handles' attribute + foreach my $name(keys %{$self}){ + if(!exists $args{$name} && $name ne 'handles'){ + $args{$name} = $self->{$name}; + } } + return $attribute_class->new($self->name, %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), @_); - $self->create($class, $name, %args); + Carp::cluck("$self->clone_parent has been deprecated." + . "Use \$meta->add_attribute and \$attr->install_accessors instead.") + if Mouse::Util::_MOUSE_VERBOSE; + + $self->clone_and_inherited_args($class, $name, %args); } -sub get_parent_args { +sub get_parent_args { # DEPRECATED my $self = shift; my $class = shift; my $name = shift; @@ -313,6 +303,121 @@ 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 { $_ => $_ } + grep { !Mouse::Object->can($_) && $_ =~ $handles } + Mouse::Util::is_a_metarole($meta) + ? $meta->get_method_list + : $meta->get_all_method_names; + } + else { + $self->throw_error("Unable to canonicalize the 'handles' option with $handles"); + } +} + +sub associate_method{ + my ($attribute, $method_name) = @_; + $attribute->{associated_methods}++; + return; +} + + +sub delegation_metaclass() { 'Mouse::Meta::Method::Delegation' } + +sub install_accessors{ + my($attribute) = @_; + + my $metaclass = $attribute->associated_class; + my $accessor_class = $attribute->accessor_metaclass; + + foreach my $type(qw(accessor reader writer predicate clearer)){ + if(exists $attribute->{$type}){ + my $generator = '_generate_' . $type; + my $code = $accessor_class->$generator($attribute, $metaclass); + $metaclass->add_method($attribute->{$type} => $code); + $attribute->associate_method($attribute->{$type}); + } + } + + # install delegation + if(exists $attribute->{handles}){ + my $delegation_class = $attribute->delegation_metaclass; + 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 = $delegation_class->_generate_delegation($attribute, $metaclass, + $reader, $handle_name, $method_to_call); + + $metaclass->add_method($handle_name => $code); + $attribute->associate_method($handle_name); + } + } + + + if($attribute->can('create') != \&create){ + # backword compatibility + $attribute->create($metaclass, $attribute->name, %{$attribute}); + } + + return; +} + sub throw_error{ my $self = shift; @@ -326,90 +431,149 @@ __END__ =head1 NAME -Mouse::Meta::Attribute - attribute metaclass +Mouse::Meta::Attribute - The Mouse attribute metaclass + +=head1 VERSION + +This document describes Mouse version 0.40_08 =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 >> + +Setting this to true makes the attribute lazy and provides a number of +default methods. + + has 'size' => ( + is => 'ro', + lazy_build => 1, + ); + +is equivalent to this: + + has 'size' => ( + is => 'ro', + lazy => 1, + builder => '_build_size', + clearer => 'clear_size', + predicate => 'has_size', + ); -=head2 canonicalize_args Name, %args -> %args +=back -Canonicalizes some arguments to create. In particular, C is -canonicalized into C, C, etc. +=head2 C<< associate_method(MethodName) >> -=head2 validate_args Name, \%args -> 1 | ERROR +Associates a method with the attribute. Typically, this is called internally +when an attribute generates its accessors. -Checks that the arguments to create the attribute (ie those specified by -C) are valid. +Currently the argument I is ignored in Mouse. -=head2 clone_parent OwnerClass, AttributeName, %args -> Mouse::Meta::Attribute +=head2 C<< verify_against_type_constraint(Item) -> TRUE | ERROR >> -Creates a new attribute in OwnerClass, inheriting options from parent classes. +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 - \ No newline at end of file