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=4feac11dd03d1b2e5118ce42ee7d5d153bf715f2;hp=77d935a03711d566f57d795db5a413d1b4c6ddab;hb=4a29b63e8d38182682b0c13ac0260f708cb1b89f;hpb=7b133c927969b2e9233a51c6be5caed54c88915e diff --git a/lib/Mouse/Meta/Attribute.pm b/lib/Mouse/Meta/Attribute.pm index 77d935a..4feac11 100644 --- a/lib/Mouse/Meta/Attribute.pm +++ b/lib/Mouse/Meta/Attribute.pm @@ -2,27 +2,155 @@ package Mouse::Meta::Attribute; use strict; use warnings; +use Carp (); + +use Mouse::Util qw(:meta); + use Mouse::Meta::TypeConstraint; use Mouse::Meta::Method::Accessor; -sub new { - my ($class, $name, %options) = @_; +sub _process_options{ + my($class, $name, $args) = @_; + + # taken from Class::MOP::Attribute::new - $options{name} = $name; + defined($name) + or $class->throw_error('You must provide a name for the attribute'); - $options{init_arg} = $name - unless exists $options{init_arg}; + if(!exists $args->{init_arg}){ + $args->{init_arg} = $name; + } + + # 'required' requires eigher 'init_arg', 'builder', or 'default' + my $can_be_required = defined( $args->{init_arg} ); - my $is = $options{is} ||= ''; + if(exists $args->{builder}){ + $class->throw_error('builder must be a defined scalar value which is a method name') + if ref $args->{builder} || !(defined $args->{builder}); - if($is eq 'rw'){ - $options{accessor} = $name if !exists $options{accessor}; + $can_be_required++; } - elsif($is eq 'ro'){ - $options{reader} = $name if !exists $options{reader}; + 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++; } - bless \%options, $class; + 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_args-> + + if(exists $args->{is}){ + my $is = $args->{is}; + + if($is eq 'ro'){ + $args->{reader} ||= $name; + } + elsif($is eq 'rw'){ + if(exists $args->{writer}){ + $args->{reader} ||= $name; + } + else{ + $args->{accessor} ||= $name; + } + } + elsif($is eq 'bare'){ + # do nothing, but don't complain (later) about missing methods + } + else{ + $is = 'undef' if !defined $is; + $class->throw_error("I do not understand this option (is => $is) on attribute ($name)"); + } + } + + my $tc; + if(exists $args->{isa}){ + $args->{type_constraint} = Mouse::Util::TypeConstraints::find_or_create_isa_type_constraint($args->{isa}); + } + elsif(exists $args->{does}){ + # TODO + # $args->{type_constraint} = Mouse::Util::TypeConstraints::find_or_create_does_type_constraint($args->{does}); + } + $tc = $args->{type_constraint}; + + if($args->{coerce}){ + defined($tc) + || $class->throw_error("You cannot have coercion without specifying a type constraint on attribute ($name)"); + + $args->{weak_ref} + && $class->throw_error("You cannot have a weak reference to a coerced value on attribute ($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 ($args->{auto_deref}) { + defined($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)"); + } + + if (exists $args->{trigger}) { + ('CODE' eq ref $args->{trigger}) + || $class->throw_error("Trigger must be a CODE ref on attribute ($name)"); + } + + 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"); + } + + # XXX: for backward compatibility (with method modifiers) + if($class->can('canonicalize_args') != \&canonicalize_args){ + %{$args} = $class->canonicalize_args($name, %{$args}); + } + return; +} + +sub new { + my $class = shift; + my $name = shift; + + my %args = (@_ == 1) ? %{ $_[0] } : @_; + + $class->_process_options($name, \%args); + + $args{name} = $name; + + my $instance = bless \%args, $class; + + # extra attributes + if($class ne __PACKAGE__){ + $class->meta->_initialize_instance($instance,\%args); + } + +# XXX: there is no fast way to check attribute validity +# my @bad = ...; +# if(@bad){ +# @bad = sort @bad; +# Carp::cluck("Found unknown argument(s) passed to '$name' attribute constructor in '$class': @bad"); +# } + + return $instance } # readers @@ -45,14 +173,14 @@ 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 find_type_constraint { - Carp::carp("This method was deprecated"); - $_[0]->type_constraint(); -} + sub trigger { $_[0]->{trigger} } sub builder { $_[0]->{builder} } sub should_auto_deref { $_[0]->{auto_deref} } -sub should_coerce { $_[0]->{should_coerce} } +sub should_coerce { $_[0]->{coerce} } + +sub get_read_method { $_[0]->{reader} || $_[0]->{accessor} } +sub get_write_method { $_[0]->{writer} || $_[0]->{accessor} } # predicates @@ -68,112 +196,65 @@ 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 { $_[0]->{_create_args} = $_[1] if @_ > 1; $_[0]->{_create_args} } -sub accessor_metaclass { 'Mouse::Meta::Method::Accessor' } +sub interpolate_class{ + my($class, $name, $args) = @_; -sub create { - my ($self, $class, $name, %args) = @_; - - $args{name} = $name; - $args{associated_class} = $class; - - %args = $self->canonicalize_args($name, %args); - $self->validate_args($name, \%args); - - $args{should_coerce} = delete $args{coerce} - if exists $args{coerce}; - - if (exists $args{isa}) { - my $type_constraint = delete $args{isa}; - $args{type_constraint}= Mouse::Util::TypeConstraints::find_or_create_isa_type_constraint($type_constraint); + 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); + 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($associated_methods == 0 && ($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?)}); + if (@traits) { + $class = Mouse::Meta::Class->create_anon_class( + superclasses => [ $class ], + roles => \@traits, + cache => 1, + )->name; + } } - return $attribute; + return( $class, @traits ); } -sub canonicalize_args { - my $self = shift; - my $name = shift; - my %args = @_; +sub canonicalize_args{ + my ($self, $name, %args) = @_; - if ($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}); - } - else { - $args{clearer} = "clear_${name}" if !exists($args{clearer}); - $args{predicate} = "has_${name}" if !exists($args{predicate}); - } - } + Carp::cluck("$self->canonicalize_args has been deprecated." + . "Use \$self->_process_options instead."); return %args; } -sub validate_args { - my $self = shift; - my $name = shift; - my $args = shift; - - $self->throw_error("You can not use lazy_build and default for the same attribute ($name)") - if $args->{lazy_build} && exists $args->{default}; - - $self->throw_error("You cannot have lazy attribute ($name) without specifying a default value for it") - if $args->{lazy} - && !exists($args->{default}) - && !exists($args->{builder}); - - $self->throw_error("References are not allowed as default values, you must wrap the default of '$name' in a CODE reference (ex: sub { [] } and not [])") - if ref($args->{default}) - && ref($args->{default}) ne 'CODE'; - - $self->throw_error("You cannot auto-dereference without specifying a type constraint on attribute ($name)") - if $args->{auto_deref} && !exists($args->{isa}); - - $self->throw_error("You cannot auto-dereference anything other than a ArrayRef or HashRef on attribute ($name)") - if $args->{auto_deref} - && $args->{isa} !~ /^(?:ArrayRef|HashRef)(?:\[.*\])?$/; - - if ($args->{trigger}) { - if (ref($args->{trigger}) eq 'HASH') { - $self->throw_error("HASH-based form of trigger has been removed. Only the coderef form of triggers are now supported."); - } +sub create { + my ($self, $class, $name, %args) = @_; - $self->throw_error("Trigger must be a CODE ref on attribute ($name)") - if ref($args->{trigger}) ne 'CODE'; - } + Carp::cluck("$self->create has been deprecated." + . "Use \$meta->add_attribute and \$attr->install_accessors instead."); - return 1; + # noop + return $self; } sub verify_against_type_constraint { @@ -195,7 +276,7 @@ sub verify_type_constraint_error { sub coerce_constraint { ## my($self, $value) = @_; my $type = $_[0]->{type_constraint} or return $_[1]; - return Mouse::Util::TypeConstraints->typecast_constraints($_[0]->associated_class->name, $_[0]->type_constraint, $_[1]); + return Mouse::Util::TypeConstraints->typecast_constraints($_[0]->associated_class->name, $type, $_[1]); } sub _canonicalize_handles { @@ -213,13 +294,24 @@ sub _canonicalize_handles { } } +sub clone_and_inherit_options{ + my $self = shift; + my $name = shift; + + return ref($self)->new($name, %{$self}, (@_ == 1) ? %{$_[0]} : @_); +} + sub clone_parent { my $self = shift; my $class = shift; my $name = shift; my %args = ($self->get_parent_args($class, $name), @_); - $self->create($class, $name, %args); + Carp::cluck("$self->clone_parent has been deprecated." + . "Use \$meta->add_attribute and \$attr->install_accessors instead."); + + + $self->clone_and_inherited_args($class, $name, %args); } sub get_parent_args { @@ -236,6 +328,29 @@ sub get_parent_args { $self->throw_error("Could not find an attribute by the name of '$name' to inherit from"); } +sub install_accessors{ + my($attribute) = @_; + + my $metaclass = $attribute->{associated_class}; + + foreach my $type(qw(accessor reader writer predicate clearer handles)){ + if(exists $attribute->{$type}){ + my $installer = '_install_' . $type; + + Mouse::Meta::Method::Accessor->$installer($attribute, $attribute->{$type}, $metaclass); + + $attribute->{associated_methods}++; + } + } + + if($attribute->can('create') != \&create){ + # backword compatibility + $attribute->create($metaclass, $attribute->name, %{$attribute}); + } + + return; +} + sub throw_error{ my $self = shift; @@ -253,85 +368,123 @@ Mouse::Meta::Attribute - attribute metaclass =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. -=head2 canonicalize_args Name, %args -> %args + has 'size' => ( + is => 'ro', + lazy_build => 1, + ); -Canonicalizes some arguments to create. In particular, C is -canonicalized into C, C, etc. +is equivalent to this: -=head2 validate_args Name, \%args -> 1 | ERROR + has 'size' => ( + is => 'ro', + lazy => 1, + builder => '_build_size', + clearer => 'clear_size', + predicate => 'has_size', + ); -Checks that the arguments to create the attribute (ie those specified by -C) are valid. +=back + +=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 clone_parent OwnerClass, AttributeName, %args -> Mouse::Meta::Attribute +=head2 C<< clone_and_inherit_options(options) -> Mouse::Meta::Attribute >> Creates a new attribute in OwnerClass, inheriting options from parent classes. Accessors and helper methods are installed. Some error checking is done. -=head2 get_parent_args OwnerClass, AttributeName -> Hash +=head1 SEE ALSO -Returns the options that the parent class of C used for attribute -C. +L =cut