X-Git-Url: http://git.shadowcat.co.uk/gitweb/gitweb.cgi?a=blobdiff_plain;f=lib%2FMoose%2FMeta%2FAttribute.pm;h=d83516834ac67689ae3319319107da0aa5d3134b;hb=a532c4ac93ebdcbd09cd455dbb49caf8a7de1912;hp=111c6469acfe4419949480820d57b3d723ddea18;hpb=688fcdda5c37b86784f8a923b636bdbbf47181d5;p=gitmo%2FMoose.git diff --git a/lib/Moose/Meta/Attribute.pm b/lib/Moose/Meta/Attribute.pm index 111c646..d835168 100644 --- a/lib/Moose/Meta/Attribute.pm +++ b/lib/Moose/Meta/Attribute.pm @@ -4,15 +4,15 @@ package Moose::Meta::Attribute; use strict; use warnings; -use Scalar::Util 'blessed', 'weaken', 'reftype'; -use Carp 'confess'; -use Sub::Name 'subname'; +use Scalar::Util 'blessed', 'weaken'; use overload (); -our $VERSION = '0.18'; +our $VERSION = '0.71_01'; our $AUTHORITY = 'cpan:STEVAN'; use Moose::Meta::Method::Accessor; +use Moose::Meta::Method::Delegation; +use Moose::Util (); use Moose::Util::TypeConstraints (); use base 'Class::MOP::Attribute'; @@ -46,79 +46,256 @@ __PACKAGE__->meta->add_attribute('documentation' => ( reader => 'documentation', predicate => 'has_documentation', )); +__PACKAGE__->meta->add_attribute('traits' => ( + reader => 'applied_traits', + predicate => 'has_applied_traits', +)); + +# we need to have a ->does method in here to +# more easily support traits, and the introspection +# of those traits. We extend the does check to look +# for metatrait aliases. +sub does { + my ($self, $role_name) = @_; + my $name = eval { + Moose::Util::resolve_metatrait_alias(Attribute => $role_name) + }; + return 0 if !defined($name); # failed to load class + return $self->Moose::Object::does($name); +} + +sub throw_error { + my $self = shift; + my $class = ( ref $self && $self->associated_class ) || "Moose::Meta::Class"; + unshift @_, "message" if @_ % 2 == 1; + unshift @_, attr => $self if ref $self; + unshift @_, $class; + my $handler = $class->can("throw_error"); # to avoid incrementing depth by 1 + goto $handler; +} sub new { my ($class, $name, %options) = @_; - $class->_process_options($name, \%options); + $class->_process_options($name, \%options) unless $options{__hack_no_process_options}; # used from clone()... YECHKKK FIXME ICKY YUCK GROSS return $class->SUPER::new($name, %options); } +sub interpolate_class_and_new { + my ($class, $name, @args) = @_; + + my ( $new_class, @traits ) = $class->interpolate_class(@args); + + $new_class->new($name, @args, ( scalar(@traits) ? ( traits => \@traits ) : () ) ); +} + +sub interpolate_class { + my ($class, %options) = @_; + + $class = ref($class) || $class; + + if ( my $metaclass_name = delete $options{metaclass} ) { + my $new_class = Moose::Util::resolve_metaclass_alias( Attribute => $metaclass_name ); + + if ( $class ne $new_class ) { + if ( $new_class->can("interpolate_class") ) { + return $new_class->interpolate_class(%options); + } else { + $class = $new_class; + } + } + } + + my @traits; + + if (my $traits = $options{traits}) { + my $i = 0; + while ($i < @$traits) { + my $trait = $traits->[$i++]; + next if ref($trait); # options to a trait we discarded + + $trait = Moose::Util::resolve_metatrait_alias(Attribute => $trait) + || $trait; + + next if $class->does($trait); + + push @traits, $trait; + + # are there options? + push @traits, $traits->[$i++] + if $traits->[$i] && ref($traits->[$i]); + } + + if (@traits) { + my $anon_class = Moose::Meta::Class->create_anon_class( + superclasses => [ $class ], + roles => [ @traits ], + cache => 1, + ); + + $class = $anon_class->name; + } + } + + return ( wantarray ? ( $class, @traits ) : $class ); +} + +# ... + +my @legal_options_for_inheritance = qw( + default coerce required + documentation lazy handles + builder type_constraint + definition_context +); + +sub legal_options_for_inheritance { @legal_options_for_inheritance } + +# NOTE/TODO +# This method *must* be able to handle +# Class::MOP::Attribute instances as +# well. Yes, I know that is wrong, but +# apparently we didn't realize it was +# doing that and now we have some code +# which is dependent on it. The real +# solution of course is to push this +# feature back up into Class::MOP::Attribute +# but I not right now, I am too lazy. +# However if you are reading this and +# looking for something to do,.. please +# be my guest. +# - stevan sub clone_and_inherit_options { my ($self, %options) = @_; - # you can change default, required, coerce, documentation and lazy + + my %copy = %options; + my %actual_options; - foreach my $legal_option (qw(default coerce required documentation lazy)) { + + # NOTE: + # we may want to extends a Class::MOP::Attribute + # in which case we need to be able to use the + # core set of legal options that have always + # been here. But we allows Moose::Meta::Attribute + # instances to changes them. + # - SL + my @legal_options = $self->can('legal_options_for_inheritance') + ? $self->legal_options_for_inheritance + : @legal_options_for_inheritance; + + foreach my $legal_option (@legal_options) { if (exists $options{$legal_option}) { $actual_options{$legal_option} = $options{$legal_option}; delete $options{$legal_option}; } - } + } - # handles can only be added, not changed - if ($options{handles}) { - confess "You can only add the 'handles' option, you cannot change it" - if $self->has_handles; - $actual_options{handles} = $options{handles}; - delete $options{handles}; - } - - # isa can be changed, but only if the - # new type is a subtype if ($options{isa}) { my $type_constraint; if (blessed($options{isa}) && $options{isa}->isa('Moose::Meta::TypeConstraint')) { $type_constraint = $options{isa}; } else { - $type_constraint = Moose::Util::TypeConstraints::find_or_create_type_constraint( - $options{isa} - ); + $type_constraint = Moose::Util::TypeConstraints::find_or_create_isa_type_constraint($options{isa}); (defined $type_constraint) - || confess "Could not find the type constraint '" . $options{isa} . "'"; + || $self->throw_error("Could not find the type constraint '" . $options{isa} . "'", data => $options{isa}); } - # NOTE: - # check here to see if the new type - # is a subtype of the old one - ($type_constraint->is_subtype_of($self->type_constraint->name)) - || confess "New type constraint setting must be a subtype of inherited one" - # iff we have a type constraint that is ... - if $self->has_type_constraint; - # then we use it :) + $actual_options{type_constraint} = $type_constraint; delete $options{isa}; } + + if ($options{does}) { + my $type_constraint; + if (blessed($options{does}) && $options{does}->isa('Moose::Meta::TypeConstraint')) { + $type_constraint = $options{does}; + } + else { + $type_constraint = Moose::Util::TypeConstraints::find_or_create_does_type_constraint($options{does}); + (defined $type_constraint) + || $self->throw_error("Could not find the type constraint '" . $options{does} . "'", data => $options{does}); + } + + $actual_options{type_constraint} = $type_constraint; + delete $options{does}; + } + + # NOTE: + # this doesn't apply to Class::MOP::Attributes, + # so we can ignore it for them. + # - SL + if ($self->can('interpolate_class')) { + ( $actual_options{metaclass}, my @traits ) = $self->interpolate_class(%options); + + my %seen; + my @all_traits = grep { $seen{$_}++ } @{ $self->applied_traits || [] }, @traits; + $actual_options{traits} = \@all_traits if @all_traits; + + delete @options{qw(metaclass traits)}; + } + (scalar keys %options == 0) - || confess "Illegal inherited options => (" . (join ', ' => keys %options) . ")"; + || $self->throw_error("Illegal inherited options => (" . (join ', ' => keys %options) . ")", data => \%options); + + $self->clone(%actual_options); } +sub clone { + my ( $self, %params ) = @_; + + my $class = $params{metaclass} || ref $self; + + if ( 0 and $class eq ref $self ) { + return $self->SUPER::clone(%params); + } else { + my ( @init, @non_init ); + + foreach my $attr ( grep { $_->has_value($self) } $self->meta->compute_all_applicable_attributes ) { + push @{ $attr->has_init_arg ? \@init : \@non_init }, $attr; + } + + my %new_params = ( ( map { $_->init_arg => $_->get_value($self) } @init ), %params ); + + my $name = delete $new_params{name}; + + my $clone = $class->new($name, %new_params, __hack_no_process_options => 1 ); + + foreach my $attr ( @non_init ) { + $attr->set_value($clone, $attr->get_value($self)); + } + + + return $clone; + } +} + sub _process_options { my ($class, $name, $options) = @_; if (exists $options->{is}) { + + ### ------------------------- + ## is => ro, writer => _foo # turns into (reader => foo, writer => _foo) as before + ## is => rw, writer => _foo # turns into (reader => foo, writer => _foo) + ## is => rw, accessor => _foo # turns into (accessor => _foo) + ## is => ro, accessor => _foo # error, accesor is rw + ### ------------------------- + if ($options->{is} eq 'ro') { + $class->throw_error("Cannot define an accessor name on a read-only attribute, accessors are read/write", data => $options) + if exists $options->{accessor}; $options->{reader} ||= $name; - (!exists $options->{trigger}) - || confess "Cannot have a trigger on a read-only attribute"; } elsif ($options->{is} eq 'rw') { - $options->{accessor} = $name; - ((reftype($options->{trigger}) || '') eq 'CODE') - || confess "Trigger must be a CODE ref" - if exists $options->{trigger}; + if ($options->{writer}) { + $options->{reader} ||= $name; + } + else { + $options->{accessor} ||= $name; + } } else { - confess "I do not understand this option (is => " . $options->{is} . ")" + $class->throw_error("I do not understand this option (is => " . $options->{is} . ") on attribute ($name)", data => $options->{is}); } } @@ -126,10 +303,10 @@ sub _process_options { if (exists $options->{does}) { if (eval { $options->{isa}->can('does') }) { ($options->{isa}->does($options->{does})) - || confess "Cannot have an isa option and a does option if the isa does not do the does"; + || $class->throw_error("Cannot have an isa option and a does option if the isa does not do the does on attribute ($name)", data => $options); } else { - confess "Cannot have an isa option which cannot ->does()"; + $class->throw_error("Cannot have an isa option which cannot ->does() on attribute ($name)", data => $options); } } @@ -138,12 +315,7 @@ sub _process_options { $options->{type_constraint} = $options->{isa}; } else { - $options->{type_constraint} = Moose::Util::TypeConstraints::find_or_create_type_constraint( - $options->{isa} => { - parent => Moose::Util::TypeConstraints::find_type_constraint('Object'), - constraint => sub { $_[0]->isa($options->{isa}) } - } - ); + $options->{type_constraint} = Moose::Util::TypeConstraints::find_or_create_isa_type_constraint($options->{isa}); } } elsif (exists $options->{does}) { @@ -152,34 +324,32 @@ sub _process_options { $options->{type_constraint} = $options->{does}; } else { - $options->{type_constraint} = Moose::Util::TypeConstraints::find_or_create_type_constraint( - $options->{does} => { - parent => Moose::Util::TypeConstraints::find_type_constraint('Role'), - constraint => sub { - Moose::Util::does_role($_[0], $options->{does}) - } - } - ); + $options->{type_constraint} = Moose::Util::TypeConstraints::find_or_create_does_type_constraint($options->{does}); } } if (exists $options->{coerce} && $options->{coerce}) { (exists $options->{type_constraint}) - || confess "You cannot have coercion without specifying a type constraint"; - confess "You cannot have a weak reference to a coerced value" + || $class->throw_error("You cannot have coercion without specifying a type constraint on attribute ($name)", data => $options); + $class->throw_error("You cannot have a weak reference to a coerced value on attribute ($name)", data => $options) if $options->{weak_ref}; } + if (exists $options->{trigger}) { + ('CODE' eq ref $options->{trigger}) + || $class->throw_error("Trigger must be a CODE ref on attribute ($name)", data => $options->{trigger}); + } + if (exists $options->{auto_deref} && $options->{auto_deref}) { (exists $options->{type_constraint}) - || confess "You cannot auto-dereference without specifying a type constraint"; + || $class->throw_error("You cannot auto-dereference without specifying a type constraint on attribute ($name)", data => $options); ($options->{type_constraint}->is_a_type_of('ArrayRef') || $options->{type_constraint}->is_a_type_of('HashRef')) - || confess "You cannot auto-dereference anything other than a ArrayRef or HashRef"; + || $class->throw_error("You cannot auto-dereference anything other than a ArrayRef or HashRef on attribute ($name)", data => $options); } if (exists $options->{lazy_build} && $options->{lazy_build} == 1) { - confess("You can not use lazy_build and default for the same attribute") + $class->throw_error("You can not use lazy_build and default for the same attribute ($name)", data => $options) if exists $options->{default}; $options->{lazy} = 1; $options->{required} = 1; @@ -196,11 +366,11 @@ sub _process_options { if (exists $options->{lazy} && $options->{lazy}) { (exists $options->{default} || defined $options->{builder} ) - || confess "You cannot have lazy attribute without specifying a default value for it"; + || $class->throw_error("You cannot have lazy attribute ($name) without specifying a default value for it", data => $options); } if ( $options->{required} && !( ( !exists $options->{init_arg} || defined $options->{init_arg} ) || exists $options->{default} || defined $options->{builder} ) ) { - confess "You cannot have a required attribute without a default, builder, or an init_arg"; + $class->throw_error("You cannot have a required attribute ($name) without a default, builder, or an init_arg", data => $options); } } @@ -220,7 +390,7 @@ sub initialize_instance_slot { # skip it if it's lazy return if $self->is_lazy; # and die if it's required and doesn't have a default value - confess "Attribute (" . $self->name . ") is required" + $self->throw_error("Attribute (" . $self->name . ") is required", object => $instance, data => $params) if $self->is_required && !$self->has_default && !$self->has_builder; # if nothing was in the %params, we can use the @@ -230,13 +400,8 @@ sub initialize_instance_slot { $value_is_set = 1; } elsif ($self->has_builder) { - if (my $builder = $instance->can($self->builder)){ - $val = $instance->$builder; - $value_is_set = 1; - } - else { - confess(blessed($instance)." does not support builder method '".$self->builder."' for attribute '" . $self->name . "'"); - } + $val = $self->_call_builder($instance); + $value_is_set = 1; } } @@ -247,28 +412,77 @@ sub initialize_instance_slot { if ($self->should_coerce && $type_constraint->has_coercion) { $val = $type_constraint->coerce($val); } - (defined($type_constraint->check($val))) - || confess "Attribute (" - . $self->name - . ") does not pass the type constraint because: " - . $type_constraint->get_message($val); + $self->verify_against_type_constraint($val, instance => $instance); } - $meta_instance->set_slot_value($instance, $self->name, $val); + $self->set_initial_value($instance, $val); $meta_instance->weaken_slot_value($instance, $self->name) if ref $val && $self->is_weak_ref; } +sub _call_builder { + my ( $self, $instance ) = @_; + + my $builder = $self->builder(); + + return $instance->$builder() + if $instance->can( $self->builder ); + + $self->throw_error( blessed($instance) + . " does not support builder method '" + . $self->builder + . "' for attribute '" + . $self->name + . "'", + object => $instance, + ); +} + ## Slot management +# FIXME: +# this duplicates too much code from +# Class::MOP::Attribute, we need to +# refactor these bits eventually. +# - SL +sub _set_initial_slot_value { + my ($self, $meta_instance, $instance, $value) = @_; + + my $slot_name = $self->name; + + return $meta_instance->set_slot_value($instance, $slot_name, $value) + unless $self->has_initializer; + + my ($type_constraint, $can_coerce); + if ($self->has_type_constraint) { + $type_constraint = $self->type_constraint; + $can_coerce = ($self->should_coerce && $type_constraint->has_coercion); + } + + my $callback = sub { + my $val = shift; + if ($type_constraint) { + $val = $type_constraint->coerce($val) + if $can_coerce; + $self->verify_against_type_constraint($val, object => $instance); + } + $meta_instance->set_slot_value($instance, $slot_name, $val); + }; + + my $initializer = $self->initializer; + + # most things will just want to set a value, so make it first arg + $instance->$initializer($value, $callback, $self); +} + sub set_value { - my ($self, $instance, $value) = @_; + my ($self, $instance, @args) = @_; + my $value = $args[0]; my $attr_name = $self->name; - if ($self->is_required) { - defined($value) - || confess "Attribute ($attr_name) is required, so cannot be set to undef"; + if ($self->is_required and not @args) { + $self->throw_error("Attribute ($attr_name) is required", object => $instance); } if ($self->has_type_constraint) { @@ -279,11 +493,10 @@ sub set_value { $value = $type_constraint->coerce($value); } $type_constraint->_compiled_type_constraint->($value) - || confess "Attribute (" + || $self->throw_error("Attribute (" . $self->name . ") does not pass the type constraint because " - . $type_constraint->get_message($value) - if defined($value); + . $type_constraint->get_message($value), object => $instance, data => $value); } my $meta_instance = Class::MOP::Class->initialize(blessed($instance)) @@ -296,7 +509,7 @@ sub set_value { } if ($self->has_trigger) { - $self->trigger->($instance, $value, $self); + $self->trigger->($instance, $value); } } @@ -305,26 +518,19 @@ sub get_value { if ($self->is_lazy) { unless ($self->has_value($instance)) { + my $value; if ($self->has_default) { - my $default = $self->default($instance); - $self->set_value($instance, $default); + $value = $self->default($instance); + } elsif ( $self->has_builder ) { + $value = $self->_call_builder($instance); } - if ( $self->has_builder ){ - if (my $builder = $instance->can($self->builder)){ - $self->set_value($instance, $instance->$builder); - } - else { - confess(blessed($instance) - . " does not support builder method '" - . $self->builder - . "' for attribute '" - . $self->name - . "'"); - } - } - else { - $self->set_value($instance, undef); + if ($self->has_type_constraint) { + my $type_constraint = $self->type_constraint; + $value = $type_constraint->coerce($value) + if ($self->should_coerce); + $self->verify_against_type_constraint($value); } + $self->set_initial_value($instance, $value); } } @@ -343,7 +549,7 @@ sub get_value { return wantarray ? %{ $rv } : $rv; } else { - confess "Can not auto de-reference the type constraint '" . $type_constraint->name . "'"; + $self->throw_error("Can not auto de-reference the type constraint '" . $type_constraint->name . "'", object => $instance, type_constraint => $type_constraint); } } @@ -360,58 +566,61 @@ sub accessor_metaclass { 'Moose::Meta::Method::Accessor' } sub install_accessors { my $self = shift; $self->SUPER::install_accessors(@_); + $self->install_delegation if $self->has_handles; + return; +} - if ($self->has_handles) { +sub remove_accessors { + my $self = shift; + $self->SUPER::remove_accessors(@_); + $self->remove_delegation if $self->has_handles; + return; +} + +sub install_delegation { + my $self = shift; + + # NOTE: + # Here we canonicalize the 'handles' option + # this will sort out any details and always + # return an hash of methods which we want + # to delagate to, see that method for details + my %handles = $self->_canonicalize_handles; - # NOTE: - # Here we canonicalize the 'handles' option - # this will sort out any details and always - # return an hash of methods which we want - # to delagate to, see that method for details - my %handles = $self->_canonicalize_handles(); - - # find the accessor method for this attribute - my $accessor = $self->get_read_method_ref; - # then unpack it if we need too ... - $accessor = $accessor->body if blessed $accessor; - - # install the delegation ... - my $associated_class = $self->associated_class; - foreach my $handle (keys %handles) { - my $method_to_call = $handles{$handle}; - my $class_name = $associated_class->name; - my $name = "${class_name}::${handle}"; + + # install the delegation ... + my $associated_class = $self->associated_class; + foreach my $handle (keys %handles) { + my $method_to_call = $handles{$handle}; + my $class_name = $associated_class->name; + my $name = "${class_name}::${handle}"; (!$associated_class->has_method($handle)) - || confess "You cannot overwrite a locally defined method ($handle) with a delegation"; + || $self->throw_error("You cannot overwrite a locally defined method ($handle) with a delegation", method_name => $handle); - # NOTE: - # handles is not allowed to delegate - # any of these methods, as they will - # override the ones in your class, which - # is almost certainly not what you want. + # NOTE: + # handles is not allowed to delegate + # any of these methods, as they will + # override the ones in your class, which + # is almost certainly not what you want. - # FIXME warn when $handle was explicitly specified, but not if the source is a regex or something - #cluck("Not delegating method '$handle' because it is a core method") and - next if $class_name->isa("Moose::Object") and $handle =~ /^BUILD|DEMOLISH$/ || Moose::Object->can($handle); + # FIXME warn when $handle was explicitly specified, but not if the source is a regex or something + #cluck("Not delegating method '$handle' because it is a core method") and + next if $class_name->isa("Moose::Object") and $handle =~ /^BUILD|DEMOLISH$/ || Moose::Object->can($handle); - if ((reftype($method_to_call) || '') eq 'CODE') { - $associated_class->add_method($handle => subname $name, $method_to_call); - } - else { - $associated_class->add_method($handle => subname $name, sub { - my $proxy = (shift)->$accessor(); - @_ = ($proxy, @_); - (defined $proxy) - || confess "Cannot delegate $handle to $method_to_call because " . - "the value of " . $self->name . " is not defined"; - goto &{ $proxy->can($method_to_call) || return }; - }); - } - } - } + my $method = $self->_make_delegation_method($handle, $method_to_call); - return; + $self->associated_class->add_method($method->name, $method); + } +} + +sub remove_delegation { + my $self = shift; + my %handles = $self->_canonicalize_handles; + my $associated_class = $self->associated_class; + foreach my $handle (keys %handles) { + $self->associated_class->remove_method($handle); + } } # private methods to help delegation ... @@ -428,7 +637,7 @@ sub _canonicalize_handles { } elsif ($handle_type eq 'Regexp') { ($self->has_type_constraint) - || confess "Cannot delegate methods based on a RegExpr without a type constraint (isa)"; + || $self->throw_error("Cannot delegate methods based on a Regexp without a type constraint (isa)", data => $handles); return map { ($_ => $_) } grep { /$handles/ } $self->_get_delegate_method_list; } @@ -436,18 +645,21 @@ sub _canonicalize_handles { return $handles->($self, $self->_find_delegate_metaclass); } else { - confess "Unable to canonicalize the 'handles' option with $handles"; + $self->throw_error("Unable to canonicalize the 'handles' option with $handles", data => $handles); } } else { + Class::MOP::load_class($handles) + unless Class::MOP::is_class_loaded($handles); + my $role_meta = eval { $handles->meta }; if ($@) { - confess "Unable to canonicalize the 'handles' option with $handles because : $@"; + $self->throw_error("Unable to canonicalize the 'handles' option with $handles because : $@", data => $handles, error => $@); } (blessed $role_meta && $role_meta->isa('Moose::Meta::Role')) - || confess "Unable to canonicalize the 'handles' option with $handles because ->meta is not a Moose::Meta::Role"; - + || $self->throw_error("Unable to canonicalize the 'handles' option with $handles because ->meta is not a Moose::Meta::Role", data => $handles); + return map { $_ => $_ } ( $role_meta->get_method_list, $role_meta->get_required_method_list @@ -473,7 +685,7 @@ sub _find_delegate_metaclass { return $role->meta; } else { - confess "Cannot find delegate metaclass for attribute " . $self->name; + $self->throw_error("Cannot find delegate metaclass for attribute " . $self->name); } } @@ -481,18 +693,54 @@ sub _get_delegate_method_list { my $self = shift; my $meta = $self->_find_delegate_metaclass; if ($meta->isa('Class::MOP::Class')) { - return map { $_->{name} } # NOTE: !never! delegate &meta - grep { $_->{class} ne 'Moose::Object' && $_->{name} ne 'meta' } - $meta->compute_all_applicable_methods; + return map { $_->name } # NOTE: !never! delegate &meta + grep { $_->package_name ne 'Moose::Object' && $_->name ne 'meta' } + $meta->get_all_methods; } elsif ($meta->isa('Moose::Meta::Role')) { return $meta->get_method_list; } else { - confess "Unable to recognize the delegate metaclass '$meta'"; + $self->throw_error("Unable to recognize the delegate metaclass '$meta'", data => $meta); } } +sub delegation_metaclass { 'Moose::Meta::Method::Delegation' } + +sub _make_delegation_method { + my ( $self, $handle_name, $method_to_call ) = @_; + + my $method_body; + + $method_body = $method_to_call + if 'CODE' eq ref($method_to_call); + + return $self->delegation_metaclass->new( + name => $handle_name, + package_name => $self->associated_class->name, + attribute => $self, + delegate_to_method => $method_to_call, + ); +} + +sub verify_against_type_constraint { + my $self = shift; + my $val = shift; + + return 1 if !$self->has_type_constraint; + + my $type_constraint = $self->type_constraint; + + $type_constraint->check($val) + || $self->throw_error("Attribute (" + . $self->name + . ") does not pass the type constraint because: " + . $type_constraint->get_message($val), data => $val, @_); +} + +package Moose::Meta::Attribute::Custom::Moose; +sub register_implementation { 'Moose::Meta::Attribute' } + 1; __END__ @@ -525,33 +773,45 @@ will behave just as L does. =item B +=item B + +=item B + =item B =item B +=item B + +=item B + +=item B + =item B +=item B + =item B =item B - eval { $point->meta->get_attribute('x')->set_value($point, 'fourty-two') }; + eval { $point->meta->get_attribute('x')->set_value($point, 'forty-two') }; if($@) { print "Oops: $@\n"; } -I +I Before setting the value, a check is made on the type constraint of the attribute, if it has one, to see if the value passes it. If the -value fails to pass, the set operation dies with a L. +value fails to pass, the set operation dies with a L. Any coercion to convert values is done before checking the type constraint. To check a value against a type constraint before setting it, fetch the attribute instance using L, fetch the type_constraint from the attribute using L -and call L. See L +and call L. See L for an example. =back @@ -563,12 +823,28 @@ creation and type coercion. =over 4 +=item B + +Delegates to C or C if there is none. + +=item B + +=item B + +When called as a class method causes interpretation of the C and +C options. + =item B This is to support the C feature, it clones an attribute from a superclass and allows a very specific set of changes to be made to the attribute. +=item B + +Whitelist with options you can change. You can overload it in your custom +metaclass to allow your options be inheritable. + =item B Returns true if this meta-attribute has a type constraint. @@ -579,6 +855,11 @@ A read-only accessor for this meta-attribute's type constraint. For more information on what you can do with this, see the documentation for L. +=item B + +Verifies that the given value is valid under this attribute's type +constraint, otherwise throws an error. + =item B Returns true if this meta-attribute performs delegation. @@ -611,14 +892,14 @@ and predicate options for you using the following convention. #If your attribute name starts with an underscore: has '_foo' => (lazy_build => 1); #is the same as - has '_foo' => (lazy => 1, required => 1, predicate => '_has_foo', clearer => '_clear_foo', builder => '_build__foo); + has '_foo' => (lazy => 1, required => 1, predicate => '_has_foo', clearer => '_clear_foo', builder => '_build__foo'); # or has '_foo' => (lazy => 1, required => 1, predicate => '_has_foo', clearer => '_clear_foo', default => sub{shift->_build__foo}); #If your attribute name does not start with an underscore: has 'foo' => (lazy_build => 1); #is the same as - has 'foo' => (lazy => 1, required => 1, predicate => 'has_foo', clearer => 'clear_foo', builder => '_build_foo); + has 'foo' => (lazy => 1, required => 1, predicate => 'has_foo', clearer => 'clear_foo', builder => '_build_foo'); # or has 'foo' => (lazy => 1, required => 1, predicate => 'has_foo', clearer => 'clear_foo', default => sub{shift->_build_foo}); @@ -662,6 +943,15 @@ in some kind of automated documentation system perhaps. Returns true if this meta-attribute has any documentation. +=item B + +This will return the ARRAY ref of all the traits applied to this +attribute, or if no traits have been applied, it returns C. + +=item B + +Returns true if this meta-attribute has any traits applied. + =back =head1 BUGS @@ -678,7 +968,7 @@ Yuval Kogman Enothingmuch@woobling.comE =head1 COPYRIGHT AND LICENSE -Copyright 2006-2008 by Infinity Interactive, Inc. +Copyright 2006-2009 by Infinity Interactive, Inc. L