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=315eaa4591e046bab9727242944d12b881ffd472;hp=dfae8b27654126fe69db85f8e75d4890a7fbcf40;hb=637d4f17e6965551c032a3115dcbbb4d8e01fbf5;hpb=a3f4f68e59a9f962a72410a3aa1ece6f1f3126b5 diff --git a/lib/Mouse/Meta/Attribute.pm b/lib/Mouse/Meta/Attribute.pm index dfae8b2..315eaa4 100644 --- a/lib/Mouse/Meta/Attribute.pm +++ b/lib/Mouse/Meta/Attribute.pm @@ -1,253 +1,353 @@ package Mouse::Meta::Attribute; -use strict; -use warnings; -require overload; +use Mouse::Util qw(:meta); # enables strict and warnings + +use Carp (); -use Carp 'confess'; -use Scalar::Util (); use Mouse::Meta::TypeConstraint; -use Mouse::Meta::Method::Accessor; + +my %valid_options = map { $_ => undef } ( + 'accessor', + 'auto_deref', + 'builder', + 'clearer', + 'coerce', + 'default', + 'documentation', + 'does', + 'handles', + 'init_arg', + 'is', + 'isa', + 'lazy', + 'lazy_build', + 'name', + 'predicate', + 'reader', + 'required', + 'traits', + 'trigger', + 'type_constraint', + 'weak_ref', + 'writer', + + # internally used + 'associated_class', + 'associated_methods', + + # Moose defines, but Mouse doesn't + #'definition_context', + #'initializer', + #'insertion_order', + + # special case for AttributeHelpers + 'provides', + 'curries', +); sub new { - my ($class, $name, %options) = @_; + my $class = shift; + my $name = shift; - $options{name} = $name; + my $args = $class->Mouse::Object::BUILDARGS(@_); - $options{init_arg} = $name - unless exists $options{init_arg}; + # XXX: for backward compatibility (with method modifiers) + if($class->can('canonicalize_args') != \&canonicalize_args){ + %{$args} = $class->canonicalize_args($name, %{$args}); + } - $options{is} ||= ''; + $class->_process_options($name, $args); - bless \%options, $class; -} + $args->{name} = $name; + + # check options + # (1) known by core + my @bad = grep{ !exists $valid_options{$_} } keys %{$args}; + + # (2) known by subclasses + if(@bad && $class ne __PACKAGE__){ + my %valid_attrs = ( + map { $_ => undef } + grep { defined } + map { $_->init_arg() } + $class->meta->get_all_attributes() + ); + @bad = grep{ !exists $valid_attrs{$_} } @bad; + } + + # (3) bad options found + if(@bad){ + @bad = sort @bad; + Carp::cluck("Found unknown argument(s) passed to '$name' attribute constructor in '$class': @bad"); + } + + my $self = bless $args, $class; + + # extra attributes + if($class ne __PACKAGE__){ + $class->meta->_initialize_object($self, $args); + } -sub name { $_[0]->{name} } -sub associated_class { $_[0]->{associated_class} } -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 predicate { $_[0]->{predicate} } -sub clearer { $_[0]->{clearer} } -sub handles { $_[0]->{handles} } -sub is_weak_ref { $_[0]->{weak_ref} } -sub init_arg { $_[0]->{init_arg} } -sub type_constraint { $_[0]->{type_constraint} } -sub find_type_constraint { - Carp::carp("This method was deprecated"); - $_[0]->type_constraint(); + return $self; } -sub trigger { $_[0]->{trigger} } -sub builder { $_[0]->{builder} } -sub should_auto_deref { $_[0]->{auto_deref} } -sub should_coerce { $_[0]->{should_coerce} } - -sub has_default { exists $_[0]->{default} } -sub has_predicate { exists $_[0]->{predicate} } -sub has_clearer { exists $_[0]->{clearer} } -sub has_handles { exists $_[0]->{handles} } -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 inlined_name { - my $self = shift; - my $name = $self->name; - my $key = "'" . $name . "'"; - return $key; -} - -sub generate_predicate { - my $attribute = shift; - my $key = $attribute->inlined_name; +sub interpolate_class{ + my($class, $args) = @_; - my $predicate = 'sub { exists($_[0]->{'.$key.'}) }'; + if(my $metaclass = delete $args->{metaclass}){ + $class = Mouse::Util::resolve_metaclass_alias( Attribute => $metaclass ); + } - my $sub = eval $predicate; - confess $@ if $@; - return $sub; -} + my @traits; + if(my $traits_ref = delete $args->{traits}){ -sub generate_clearer { - my $attribute = shift; - my $key = $attribute->inlined_name; + for (my $i = 0; $i < @{$traits_ref}; $i++) { + my $trait = Mouse::Util::resolve_metaclass_alias(Attribute => $traits_ref->[$i], trait => 1); - my $clearer = 'sub { delete($_[0]->{'.$key.'}) }'; + next if $class->does($trait); - my $sub = eval $clearer; - confess $@ if $@; - return $sub; -} + push @traits, $trait; -sub generate_handles { - my $attribute = shift; - my $reader = $attribute->name; - my %handles = $attribute->_canonicalize_handles($attribute->handles); + # are there options? + push @traits, $traits_ref->[++$i] + if ref($traits_ref->[$i+1]); + } - my %method_map; + if (@traits) { + $class = Mouse::Meta::Class->create_anon_class( + superclasses => [ $class ], + roles => \@traits, + cache => 1, + )->name; + } + } - for my $local_method (keys %handles) { - my $remote_method = $handles{$local_method}; + return( $class, @traits ); +} - my $method = 'sub { - my $self = shift; - $self->'.$reader.'->'.$remote_method.'(@_) - }'; +sub canonicalize_args{ # DEPRECATED + my ($self, $name, %args) = @_; - $method_map{$local_method} = eval $method; - confess $@ if $@; - } + Carp::cluck("$self->canonicalize_args has been deprecated." + . "Use \$self->_process_options instead."); - return \%method_map; + return %args; } -sub create { +sub create { # DEPRECATED my ($self, $class, $name, %args) = @_; - $args{name} = $name; - $args{associated_class} = $class; + Carp::cluck("$self->create has been deprecated." + . "Use \$meta->add_attribute and \$attr->install_accessors instead."); - %args = $self->canonicalize_args($name, %args); - $self->validate_args($name, \%args); + # noop + return $self; +} - $args{should_coerce} = delete $args{coerce} - if exists $args{coerce}; +sub _coerce_and_verify { + my($self, $value, $instance) = @_; - if (exists $args{isa}) { - confess "Got isa => $args{isa}, but Mouse does not yet support parameterized types for containers other than ArrayRef and HashRef (rt.cpan.org #39795)" - if $args{isa} =~ /^([^\[]+)\[.+\]$/ && - $1 ne 'ArrayRef' && - $1 ne 'HashRef' && - $1 ne 'Maybe' - ; + my $type_constraint = $self->{type_constraint}; + return $value if !defined $type_constraint; - my $type_constraint = delete $args{isa}; - $args{type_constraint}= Mouse::Util::TypeConstraints::find_or_create_isa_type_constraint($type_constraint); + if ($self->should_coerce && $type_constraint->has_coercion) { + $value = $type_constraint->coerce($value); } - my $attribute = $self->new($name, %args); + $self->verify_against_type_constraint($value); - $attribute->_create_args(\%args); + return $value; +} - $class->add_attribute($attribute); +sub verify_against_type_constraint { + my ($self, $value) = @_; - # install an accessor - if ($attribute->_is_metadata eq 'rw' || $attribute->_is_metadata eq 'ro') { - my $code = Mouse::Meta::Method::Accessor->generate_accessor_method_inline( - $attribute, - ); - $class->add_method($name => $code); - } + my $type_constraint = $self->{type_constraint}; + return 1 if !$type_constraint; + return 1 if $type_constraint->check($value); - for my $method (qw/predicate clearer/) { - my $predicate = "has_$method"; - if ($attribute->$predicate) { - my $generator = "generate_$method"; - my $coderef = $attribute->$generator; - $class->add_method($attribute->$method => $coderef); - } - } + $self->_throw_type_constraint_error($value, $type_constraint); +} - if ($attribute->has_handles) { - my $method_map = $attribute->generate_handles; - for my $method_name (keys %$method_map) { - $class->add_method($method_name => $method_map->{$method_name}); - } - } +sub _throw_type_constraint_error { + my($self, $value, $type) = @_; - return $attribute; + $self->throw_error( + sprintf q{Attribute (%s) does not pass the type constraint because: %s}, + $self->name, + $type->get_message($value), + ); } -sub canonicalize_args { +sub clone_and_inherit_options{ my $self = shift; - my $name = shift; - my %args = @_; - - if ($args{lazy_build}) { - $args{lazy} = 1; - $args{required} = 1; - $args{builder} = "_build_${name}" - if !exists($args{builder}); - if ($name =~ /^_/) { - $args{clearer} = "_clear${name}" if !exists($args{clearer}); - $args{predicate} = "_has${name}" if !exists($args{predicate}); + my $args = $self->Mouse::Object::BUILDARGS(@_); + + my($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}; } - else { - $args{clearer} = "clear_${name}" if !exists($args{clearer}); - $args{predicate} = "has_${name}" if !exists($args{predicate}); + } + + # remove temporary caches + foreach my $attr(keys %{$args}){ + if($attr =~ /\A _/xms){ + delete $args->{$attr}; } } - return %args; + return $attribute_class->new($self->name, $args); } -sub validate_args { - my $self = shift; - my $name = shift; - my $args = shift; +sub clone_parent { # DEPRECATED + my $self = shift; + my $class = shift; + my $name = shift; + my %args = ($self->get_parent_args($class, $name), @_); - confess "You can not use lazy_build and default for the same attribute ($name)" - if $args->{lazy_build} && exists $args->{default}; + Carp::cluck("$self->clone_parent has been deprecated." + . "Use \$meta->add_attribute and \$attr->install_accessors instead."); - confess "You cannot have lazy attribute ($name) without specifying a default value for it" - if $args->{lazy} - && !exists($args->{default}) - && !exists($args->{builder}); + $self->clone_and_inherited_args($class, $name, %args); +} - confess "References are not allowed as default values, you must wrap the default of '$name' in a CODE reference (ex: sub { [] } and not [])" - if ref($args->{default}) - && ref($args->{default}) ne 'CODE'; +sub get_parent_args { # DEPRECATED + my $self = shift; + my $class = shift; + my $name = shift; - confess "You cannot auto-dereference without specifying a type constraint on attribute ($name)" - if $args->{auto_deref} && !exists($args->{isa}); + for my $super ($class->linearized_isa) { + my $super_attr = $super->can("meta") && $super->meta->get_attribute($name) + or next; + return %{ $super_attr->_create_args }; + } - confess "You cannot auto-dereference anything other than a ArrayRef or HashRef on attribute ($name)" - if $args->{auto_deref} - && $args->{isa} !~ /^(?:ArrayRef|HashRef)(?:\[.*\])?$/; + $self->throw_error("Could not find an attribute by the name of '$name' to inherit from"); +} - if ($args->{trigger}) { - if (ref($args->{trigger}) eq 'HASH') { - Carp::carp "HASH-based form of trigger has been removed. Only the coderef form of triggers are now supported."; - } - confess "Trigger must be a CODE ref on attribute ($name)" - if ref($args->{trigger}) ne 'CODE'; +sub get_read_method { + return $_[0]->reader || $_[0]->accessor +} +sub get_write_method { + return $_[0]->writer || $_[0]->accessor +} + +sub _get_accessor_method_ref { + my($self, $type, $generator) = @_; + + my $metaclass = $self->associated_class + || $self->throw_error('No asocciated class for ' . $self->name); + + my $accessor = $self->$type(); + if($accessor){ + return $metaclass->get_method_body($accessor); } + else{ + return $self->accessor_metaclass->$generator($self, $metaclass); + } +} - return 1; +sub get_read_method_ref{ + my($self) = @_; + return $self->{_read_method_ref} ||= $self->_get_accessor_method_ref('get_read_method', '_generate_reader'); } -sub verify_against_type_constraint { - my ($self, $value) = @_; - my $tc = $self->type_constraint; - return 1 unless $tc; +sub get_write_method_ref{ + my($self) = @_; + return $self->{_write_method_ref} ||= $self->_get_accessor_method_ref('get_write_method', '_generate_writer'); +} + +sub set_value { + my($self, $object, $value) = @_; + return $self->get_write_method_ref()->($object, $value); +} + +sub get_value { + my($self, $object) = @_; + return $self->get_read_method_ref()->($object); +} - local $_ = $value; - return 1 if $tc->check($value); +sub has_value { + my($self, $object) = @_; + my $accessor_ref = $self->{_predicate_ref} + ||= $self->_get_accessor_method_ref('predicate', '_generate_predicate'); - $self->verify_type_constraint_error($self->name, $value, $tc); + return $accessor_ref->($object); } -sub verify_type_constraint_error { - my($self, $name, $value, $type) = @_; - Carp::confess("Attribute ($name) does not pass the type constraint because: " . $type->get_message($value)); +sub clear_value { + my($self, $object) = @_; + my $accessor_ref = $self->{_crealer_ref} + ||= $self->_get_accessor_method_ref('clearer', '_generate_clearer'); + + return $accessor_ref->($object); } -sub coerce_constraint { ## my($self, $value) = @_; - my $type = $_[0]->{type_constraint} - or return $_[1]; - return Mouse::Util::TypeConstraints->typecast_constraints($_[0]->associated_class->name, $_[0]->type_constraint, $_[1]); + +sub associate_method{ + my ($attribute, $method_name) = @_; + $attribute->{associated_methods}++; + return; } +sub install_accessors{ + my($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 %handles = $attribute->_canonicalize_handles($attribute->{handles}); + + while(my($handle, $method_to_call) = each %handles){ + $metaclass->add_method($handle => + $attribute->_make_delegation_method( + $handle, $method_to_call)); + + $attribute->associate_method($handle); + } + } + + if($attribute->can('create') != \&create){ + # backword compatibility + $attribute->create($metaclass, $attribute->name, %{$attribute}); + } + + if(!$attribute->{associated_methods} && ($attribute->{is} || '') ne 'bare'){ + Carp::cluck( + 'Attribute (' . $attribute->name . ') of class ' . $metaclass->name + . ' has no associated methods (did you mean to provide an "is" argument?)'); + } + + return; +} + +sub delegation_metaclass() { 'Mouse::Meta::Method::Delegation' } + sub _canonicalize_handles { - my $self = shift; - my $handles = shift; + my($self, $handles) = @_; if (ref($handles) eq 'HASH') { return %$handles; @@ -255,139 +355,188 @@ sub _canonicalize_handles { elsif (ref($handles) eq 'ARRAY') { return map { $_ => $_ } @$handles; } + elsif ( ref($handles) eq 'CODE' ) { + my $class_or_role = ( $self->{isa} || $self->{does} ) + || $self->throw_error( "Cannot find delegate metaclass for attribute " . $self->name ); + return $handles->( $self, Mouse::Meta::Class->initialize("$class_or_role")); + } + 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 { - confess "Unable to canonicalize the 'handles' option with $handles"; + $self->throw_error("Unable to canonicalize the 'handles' option with $handles"); } } -sub clone_parent { - my $self = shift; - my $class = shift; - my $name = shift; - my %args = ($self->get_parent_args($class, $name), @_); - - $self->create($class, $name, %args); +sub _make_delegation_method { + my($self, $handle, $method_to_call) = @_; + return Mouse::Util::load_class($self->delegation_metaclass) + ->_generate_delegation($self, $handle, $method_to_call); } -sub get_parent_args { - my $self = shift; - my $class = shift; - my $name = shift; - - for my $super ($class->linearized_isa) { - my $super_attr = $super->can("meta") && $super->meta->get_attribute($name) - or next; - return %{ $super_attr->_create_args }; - } +sub throw_error{ + my $self = shift; - confess "Could not find an attribute by the name of '$name' to inherit from"; + my $metaclass = (ref $self && $self->associated_class) || 'Mouse::Meta::Class'; + $metaclass->throw_error(@_, depth => 1); } 1; - __END__ =head1 NAME -Mouse::Meta::Attribute - attribute metaclass +Mouse::Meta::Attribute - The Mouse attribute metaclass + +=head1 VERSION + +This document describes Mouse version 0.50_03 =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: + +=over 4 + +=item C<< is => 'ro', 'rw', 'bare' >> -Creates a new attribute in OwnerClass. Accessors and helper methods are -installed. Some error checking is done. +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 name -> AttributeName +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 associated_class -> OwnerClass +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 is_required -> Bool +=item C<< isa => Type >> -=head2 default -> Item +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 has_default -> Bool +This option can also accept a L object. -=head2 is_lazy -> 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 predicate -> MethodName | Undef +=item C<< does => Role >> -=head2 has_predicate -> Bool +This is short-hand for saying that the attribute's type must be an +object which does the named role. -=head2 clearer -> MethodName | Undef +B -=head2 has_clearer -> Bool +=item C<< coerce => Bool >> -=head2 handles -> { LocalName => RemoteName } +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 has_handles -> Bool +You can make both this and the C option true. -=head2 is_weak_ref -> Bool +=item C<< trigger => CodeRef >> -=head2 init_arg -> Str +This option accepts a subroutine reference, which will be called after +the attribute is set. -=head2 type_constraint -> Str +=item C<< required => Bool >> -=head2 has_type_constraint -> 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 trigger => CODE | Undef +A required attribute must have a C, C or a +non-C C -=head2 has_trigger -> Bool +=item C<< lazy => Bool >> -=head2 builder => MethodName | Undef +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 has_builder -> Bool +=item C<< weak_ref => Bool >> -=head2 is_lazy_build => Bool +If this is true, the attribute's value will be stored as a weak +reference. -=head2 should_auto_deref -> Bool +=item C<< auto_deref => Bool >> -Informational methods. +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. -=head2 generate_accessor -> CODE +=item C<< lazy_build => Bool >> -Creates a new code reference for the attribute's accessor. +Setting this to true makes the attribute lazy and provides a number of +default methods. -=head2 generate_predicate -> CODE + has 'size' => ( + is => 'ro', + lazy_build => 1, + ); -Creates a new code reference for the attribute's predicate. +is equivalent to this: -=head2 generate_clearer -> CODE + has 'size' => ( + is => 'ro', + lazy => 1, + builder => '_build_size', + clearer => 'clear_size', + predicate => 'has_size', + ); -Creates a new code reference for the attribute's clearer. +=back -=head2 generate_handles -> { MethodName => CODE } +=head2 C<< associate_method(MethodName) >> -Creates a new code reference for each of the attribute's handles methods. +Associates a method with the attribute. Typically, this is called internally +when an attribute generates its accessors. -=head2 verify_against_type_constraint Item -> 1 | ERROR +Currently the argument I is ignored in Mouse. -Checks that the given value passes this attribute's type constraint. Returns 1 +=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 canonicalize_args Name, %args -> %args +=head2 C<< clone_and_inherit_options(options) -> Mouse::Meta::Attribute >> -Canonicalizes some arguments to create. In particular, C is -canonicalized into C, C, etc. +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 validate_args Name, \%args -> 1 | ERROR +=head2 C<< get_read_method_ref >> -Checks that the arguments to create the attribute (ie those specified by -C) are valid. +=head2 C<< get_write_method_ref >> -=head2 clone_parent OwnerClass, AttributeName, %args -> Mouse::Meta::Attribute +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. -Creates a new attribute in OwnerClass, inheriting options from parent classes. -Accessors and helper methods are installed. Some error checking is done. +=head1 SEE ALSO -=head2 get_parent_args OwnerClass, AttributeName -> Hash +L -Returns the options that the parent class of C used for attribute -C. +L =cut