use strict;
use warnings;
-use Scalar::Util 'blessed', 'weaken', 'reftype';
+use Scalar::Util 'blessed', 'weaken';
use Carp 'confess';
-use Sub::Name 'subname';
use overload ();
-our $VERSION = '0.16';
+our $VERSION = '0.53';
our $AUTHORITY = 'cpan:STEVAN';
use Moose::Meta::Method::Accessor;
+use Moose::Util ();
use Moose::Util::TypeConstraints ();
use base 'Class::MOP::Attribute';
reader => 'documentation',
predicate => 'has_documentation',
));
+__PACKAGE__->meta->add_attribute('traits' => (
+ reader => 'applied_traits',
+ predicate => 'has_applied_traits',
+));
+
+# we need to have a ->does method in here to
+# more easily support traits, and the introspection
+# of those traits. We extend the does check to look
+# for metatrait aliases.
+sub does {
+ my ($self, $role_name) = @_;
+ my $name = eval {
+ Moose::Util::resolve_metatrait_alias(Attribute => $role_name)
+ };
+ return 0 if !defined($name); # failed to load class
+ return Moose::Object::does($self, $name);
+}
sub new {
my ($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}) {
+ if ( @traits = grep { not $class->does($_) } map {
+ Moose::Util::resolve_metatrait_alias( Attribute => $_ )
+ or
+ $_
+ } @$traits ) {
+ my $anon_class = Moose::Meta::Class->create_anon_class(
+ superclasses => [ $class ],
+ roles => [ @traits ],
+ cache => 1,
+ );
+
+ $class = $anon_class->name;
+ }
+ }
+
+ return ( wantarray ? ( $class, @traits ) : $class );
+}
+
+# you can change default, required, coerce, documentation, lazy, handles, builder, type_constraint (explicitly or using isa/does), metaclass and traits
+sub legal_options_for_inheritance {
+ return qw(default coerce required documentation lazy handles builder
+ type_constraint);
+}
+
sub clone_and_inherit_options {
my ($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)) {
+ foreach my $legal_option ($self->legal_options_for_inheritance) {
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 '" . $options{isa} . "'";
}
- # NOTE:
- # check here to see if the new type
- # is a subtype of the old one
- ($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)
+ || confess "Could not find the type constraint '" . $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->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') {
+ confess "Cannot define an accessor name on a read-only attribute, accessors are read/write"
+ 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} . ")"
+ confess "I do not understand this option (is => " . $options->{is} . ") on attribute ($name)"
}
}
if (exists $options->{does}) {
if (eval { $options->{isa}->can('does') }) {
($options->{isa}->does($options->{does}))
- || confess "Cannot have an isa option and a does option if the isa does not do the does";
+ || confess "Cannot have an isa option and a does option if the isa does not do the does on attribute ($name)";
}
else {
- confess "Cannot have an isa option which cannot ->does()";
+ confess "Cannot have an isa option which cannot ->does() on attribute ($name)";
}
}
$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 $options->{does}) {
# allow for anon-subtypes here ...
if (blessed($options->{does}) && $options->{does}->isa('Moose::Meta::TypeConstraint')) {
- $options->{type_constraint} = $options->{isa};
+ $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 { $_[0]->does($options->{does}) }
- }
- );
+ $options->{type_constraint} = Moose::Util::TypeConstraints::find_or_create_does_type_constraint($options->{does});
}
}
if (exists $options->{coerce} && $options->{coerce}) {
(exists $options->{type_constraint})
- || confess "You cannot have coercion without specifying a type constraint";
- confess "You cannot have a weak reference to a coerced value"
+ || confess "You cannot have coercion without specifying a type constraint on attribute ($name)";
+ confess "You cannot have a weak reference to a coerced value on attribute ($name)"
if $options->{weak_ref};
}
+ if (exists $options->{trigger}) {
+ ('CODE' eq ref $options->{trigger})
+ || confess "Trigger must be a CODE ref on attribute ($name)";
+ }
+
if (exists $options->{auto_deref} && $options->{auto_deref}) {
(exists $options->{type_constraint})
- || confess "You cannot auto-dereference without specifying a type constraint";
+ || confess "You cannot auto-dereference without specifying a type constraint on attribute ($name)";
($options->{type_constraint}->is_a_type_of('ArrayRef') ||
$options->{type_constraint}->is_a_type_of('HashRef'))
- || confess "You cannot auto-dereference anything other than a ArrayRef or HashRef";
+ || confess "You cannot auto-dereference anything other than a ArrayRef or HashRef on attribute ($name)";
}
if (exists $options->{lazy_build} && $options->{lazy_build} == 1) {
- confess("You can not use lazy_build and default for the same attribute")
+ confess("You can not use lazy_build and default for the same attribute ($name)")
if exists $options->{default};
$options->{lazy} = 1;
$options->{required} = 1;
}
if (exists $options->{lazy} && $options->{lazy}) {
- (exists $options->{default} || exists $options->{builder} )
- || confess "You cannot have lazy attribute without specifying a default value for it";
+ (exists $options->{default} || defined $options->{builder} )
+ || confess "You cannot have lazy attribute ($name) without specifying a default value for it";
+ }
+
+ if ( $options->{required} && !( ( !exists $options->{init_arg} || defined $options->{init_arg} ) || exists $options->{default} || defined $options->{builder} ) ) {
+ confess "You cannot have a required attribute ($name) without a default, builder, or an init_arg";
}
}
my $val;
my $value_is_set;
- if (exists $params->{$init_arg}) {
+ if ( defined($init_arg) and exists $params->{$init_arg}) {
$val = $params->{$init_arg};
$value_is_set = 1;
}
if ($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 (" .
- $type_constraint->name .
- ") with '" .
- (defined $val
- ? (blessed($val) && overload::Overloaded($val)
- ? overload::StrVal($val)
- : $val)
- : 'undef') .
- "'";
- }
-
- $meta_instance->set_slot_value($instance, $self->name, $val);
+ $type_constraint->check($val)
+ || confess "Attribute ("
+ . $self->name
+ . ") does not pass the type constraint because: "
+ . $type_constraint->get_message($val);
+ }
+
+ $self->set_initial_value($instance, $val);
$meta_instance->weaken_slot_value($instance, $self->name)
if ref $val && $self->is_weak_ref;
}
## Slot management
+# FIXME:
+# this duplicates too much code from
+# Class::MOP::Attribute, we need to
+# refactor these bits eventually.
+# - SL
+sub _set_initial_slot_value {
+ my ($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;
+ $type_constraint->check($val)
+ || confess "Attribute ("
+ . $slot_name
+ . ") does not pass the type constraint because: "
+ . $type_constraint->get_message($val);
+ }
+ $meta_instance->set_slot_value($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 ($self->is_required and not @args) {
+ confess "Attribute ($attr_name) is required";
}
if ($self->has_type_constraint) {
if ($self->should_coerce) {
$value = $type_constraint->coerce($value);
- }
- defined($type_constraint->_compiled_type_constraint->($value))
- || confess "Attribute ($attr_name) does not pass the type constraint ("
- . $type_constraint->name
- . ") with "
- . (defined($value)
- ? ("'" .
- (blessed($value) && overload::Overloaded($value)
- ? overload::StrVal($value)
- : $value)
- . "'")
- : "undef")
- if defined($value);
+ }
+ $type_constraint->_compiled_type_constraint->($value)
+ || confess "Attribute ("
+ . $self->name
+ . ") does not pass the type constraint because "
+ . $type_constraint->get_message($value);
}
my $meta_instance = Class::MOP::Class->initialize(blessed($instance))
unless ($self->has_value($instance)) {
if ($self->has_default) {
my $default = $self->default($instance);
- $self->set_value($instance, $default);
- }
- if ( $self->has_builder ){
+ $self->set_initial_value($instance, $default);
+ } elsif ( $self->has_builder ) {
if (my $builder = $instance->can($self->builder)){
- $self->set_value($instance, $instance->$builder);
- }
+ $self->set_initial_value($instance, $instance->$builder);
+ }
else {
confess(blessed($instance)
. " does not support builder method '"
}
}
else {
- $self->set_value($instance, undef);
+ $self->set_initial_value($instance, undef);
}
}
}
sub install_accessors {
my $self = shift;
$self->SUPER::install_accessors(@_);
+ $self->install_delegation if $self->has_handles;
+ return;
+}
+
+sub install_delegation {
+ my $self = shift;
- if ($self->has_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();
- # 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}::${handle}";
-
- (!$associated_class->has_method($handle))
- || confess "You cannot overwrite a locally defined method ($handle) with a delegation";
+ # 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;
- # 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.
+ # 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}";
- # 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($handle);
+ (!$associated_class->has_method($handle))
+ || confess "You cannot overwrite a locally defined method ($handle) with a delegation";
- 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, @_);
- goto &{ $proxy->can($method_to_call) || return };
- });
- }
- }
- }
+ # 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.
- return;
+ # 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($handle);
+
+ if ('CODE' eq ref($method_to_call)) {
+ $associated_class->add_method($handle => Class::MOP::subname($name, $method_to_call));
+ }
+ else {
+ # NOTE:
+ # we used to do a goto here, but the
+ # goto didn't handle failure correctly
+ # (it just returned nothing), so I took
+ # that out. However, the more I thought
+ # about it, the less I liked it doing
+ # the goto, and I prefered the act of
+ # delegation being actually represented
+ # in the stack trace.
+ # - SL
+ $associated_class->add_method($handle => Class::MOP::subname($name, sub {
+ my $proxy = (shift)->$accessor();
+ (defined $proxy)
+ || confess "Cannot delegate $handle to $method_to_call because " .
+ "the value of " . $self->name . " is not defined";
+ $proxy->$method_to_call(@_);
+ }));
+ }
+ }
}
# private methods to help delegation ...
}
}
+package Moose::Meta::Attribute::Custom::Moose;
+sub register_implementation { 'Moose::Meta::Attribute' }
+
1;
__END__
=item B<new>
+=item B<clone>
+
+=item B<does>
+
=item B<initialize_instance_slot>
=item B<install_accessors>
+=item B<install_delegation>
+
=item B<accessor_metaclass>
=item B<get_value>
=over 4
+=item B<interpolate_class_and_new>
+
+=item B<interpolate_class>
+
+When called as a class method causes interpretation of the C<metaclass> and
+C<traits> options.
+
=item B<clone_and_inherit_options>
This is to support the C<has '+foo'> feature, it clones an attribute
from a superclass and allows a very specific set of changes to be made
to the attribute.
+=item B<legal_options_for_inheritance>
+
+Whitelist with options you can change. You can overload it in your custom
+metaclass to allow your options be inheritable.
+
=item B<has_type_constraint>
Returns true if this meta-attribute has a type constraint.
Returns true if this meta-attribute has any documentation.
+=item B<applied_traits>
+
+This will return the ARRAY ref of all the traits applied to this
+attribute, or if no traits have been applied, it returns C<undef>.
+
+=item B<has_applied_traits>
+
+Returns true if this meta-attribute has any traits applied.
+
=back
=head1 BUGS