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package Moo::Role;
use strict;
use Moo::_Utils qw(
_check_tracked
_getglob
_getstash
_install_coderef
_install_modifier
_install_tracked
_load_module
_name_coderef
_set_loaded
_unimport_coderefs
);
use Carp qw(croak);
use Role::Tiny ();
BEGIN { our @ISA = qw(Role::Tiny) }
BEGIN {
our @CARP_NOT = qw(
Method::Generate::Accessor
Method::Generate::Constructor
Moo::sification
Moo::_Utils
Role::Tiny
);
}
our $VERSION = '2.005005';
$VERSION =~ tr/_//d;
Moo::sification->import;
BEGIN {
*INFO = \%Role::Tiny::INFO;
*APPLIED_TO = \%Role::Tiny::APPLIED_TO;
*COMPOSED = \%Role::Tiny::COMPOSED;
*ON_ROLE_CREATE = \@Role::Tiny::ON_ROLE_CREATE;
}
our %INFO;
our %APPLIED_TO;
our %APPLY_DEFAULTS;
our %COMPOSED;
our @ON_ROLE_CREATE;
sub import {
my $target = caller;
if ($Moo::MAKERS{$target} and $Moo::MAKERS{$target}{is_class}) {
croak "Cannot import Moo::Role into a Moo class";
}
_set_loaded(caller);
goto &Role::Tiny::import;
}
sub _accessor_maker_for {
my ($class, $target) = @_;
($INFO{$target}{accessor_maker} ||= do {
Method::Generate::Accessor->new
});
}
sub _install_subs {
my ($me, $target) = @_;
my %install = $me->_gen_subs($target);
_install_tracked $target => $_ => $install{$_}
for sort keys %install;
*{_getglob("${target}::meta")} = $me->can('meta');
return;
}
sub _require_module {
_load_module($_[1]);
}
sub _gen_subs {
my ($me, $target) = @_;
return (
has => sub {
my $name_proto = shift;
my @name_proto = ref $name_proto eq 'ARRAY' ? @$name_proto : $name_proto;
if (@_ % 2 != 0) {
croak("Invalid options for " . join(', ', map "'$_'", @name_proto)
. " attribute(s): even number of arguments expected, got " . scalar @_)
}
my %spec = @_;
foreach my $name (@name_proto) {
my $spec_ref = @name_proto > 1 ? +{%spec} : \%spec;
$me->_accessor_maker_for($target)
->generate_method($target, $name, $spec_ref);
push @{$INFO{$target}{attributes}||=[]}, $name, $spec_ref;
$me->_maybe_reset_handlemoose($target);
}
},
(map {
my $type = $_;
(
$type => sub {
push @{$INFO{$target}{modifiers}||=[]}, [ $type => @_ ];
$me->_maybe_reset_handlemoose($target);
},
)
} qw(before after around)),
requires => sub {
push @{$INFO{$target}{requires}||=[]}, @_;
$me->_maybe_reset_handlemoose($target);
},
with => sub {
$me->apply_roles_to_package($target, @_);
$me->_maybe_reset_handlemoose($target);
},
);
}
push @ON_ROLE_CREATE, sub {
my $target = shift;
if ($INC{'Moo/HandleMoose.pm'} && !$Moo::sification::disabled) {
Moo::HandleMoose::inject_fake_metaclass_for($target);
}
};
# duplicate from Moo::Object
sub meta {
my $class = ref($_[0])||$_[0];
bless({ name => $class }, 'Moo::HandleMoose::FakeMetaClass');
}
sub unimport {
my $target = caller;
_unimport_coderefs($target);
}
sub _maybe_reset_handlemoose {
my ($class, $target) = @_;
if ($INC{'Moo/HandleMoose.pm'} && !$Moo::sification::disabled) {
Moo::HandleMoose::maybe_reinject_fake_metaclass_for($target);
}
}
sub _non_methods {
my $self = shift;
my ($role) = @_;
my $non_methods = $self->SUPER::_non_methods(@_);
my $all_subs = $self->_all_subs($role);
$non_methods->{$_} = $all_subs->{$_}
for _check_tracked($role, [ keys %$all_subs ]);
return $non_methods;
}
sub is_role {
my ($self, $role) = @_;
$self->_inhale_if_moose($role);
$self->SUPER::is_role($role);
}
sub _inhale_if_moose {
my ($self, $role) = @_;
my $meta;
if (!$self->SUPER::is_role($role)
and (
$INC{"Moose.pm"}
and $meta = Class::MOP::class_of($role)
and ref $meta ne 'Moo::HandleMoose::FakeMetaClass'
and $meta->isa('Moose::Meta::Role')
)
or (
Mouse::Util->can('find_meta')
and $meta = Mouse::Util::find_meta($role)
and $meta->isa('Mouse::Meta::Role')
)
) {
my $is_mouse = $meta->isa('Mouse::Meta::Role');
$INFO{$role}{methods} = {
map +($_ => $role->can($_)),
grep $role->can($_),
grep !($is_mouse && $_ eq 'meta'),
grep !$meta->get_method($_)->isa('Class::MOP::Method::Meta'),
$meta->get_method_list
};
$APPLIED_TO{$role} = {
map +($_->name => 1), $meta->calculate_all_roles
};
$INFO{$role}{requires} = [ $meta->get_required_method_list ];
$INFO{$role}{attributes} = [
map +($_ => do {
my $attr = $meta->get_attribute($_);
my $spec = { %{ $is_mouse ? $attr : $attr->original_options } };
if ($spec->{isa}) {
require Sub::Quote;
my $get_constraint = do {
my $pkg = $is_mouse
? 'Mouse::Util::TypeConstraints'
: 'Moose::Util::TypeConstraints';
_load_module($pkg);
$pkg->can('find_or_create_isa_type_constraint');
};
my $tc = $get_constraint->($spec->{isa});
my $check = $tc->_compiled_type_constraint;
my $tc_var = '$_check_for_'.Sub::Quote::sanitize_identifier($tc->name);
$spec->{isa} = Sub::Quote::quote_sub(
qq{
&${tc_var} or Carp::croak "Type constraint failed for \$_[0]"
},
{ $tc_var => \$check },
{
package => $role,
},
);
if ($spec->{coerce}) {
# Mouse has _compiled_type_coercion straight on the TC object
$spec->{coerce} = $tc->${\(
$tc->can('coercion')||sub { $_[0] }
)}->_compiled_type_coercion;
}
}
$spec;
}), $meta->get_attribute_list
];
my $mods = $INFO{$role}{modifiers} = [];
foreach my $type (qw(before after around)) {
# Mouse pokes its own internals so we have to fall back to doing
# the same thing in the absence of the Moose API method
my $map = $meta->${\(
$meta->can("get_${type}_method_modifiers_map")
or sub { shift->{"${type}_method_modifiers"} }
)};
foreach my $method (keys %$map) {
foreach my $mod (@{$map->{$method}}) {
push @$mods, [ $type => $method => $mod ];
}
}
}
$INFO{$role}{inhaled_from_moose} = 1;
$INFO{$role}{is_role} = 1;
}
}
sub _maybe_make_accessors {
my ($self, $target, $role) = @_;
my $m;
if ($INFO{$role} && $INFO{$role}{inhaled_from_moose}
or $INC{"Moo.pm"}
and $m = Moo->_accessor_maker_for($target)
and ref($m) ne 'Method::Generate::Accessor') {
$self->_make_accessors($target, $role);
}
}
sub _make_accessors_if_moose {
my ($self, $target, $role) = @_;
if ($INFO{$role} && $INFO{$role}{inhaled_from_moose}) {
$self->_make_accessors($target, $role);
}
}
sub _make_accessors {
my ($self, $target, $role) = @_;
my $acc_gen = ($Moo::MAKERS{$target}{accessor} ||= do {
Method::Generate::Accessor->new
});
my $con_gen = $Moo::MAKERS{$target}{constructor};
my @attrs = @{$INFO{$role}{attributes}||[]};
while (my ($name, $spec) = splice @attrs, 0, 2) {
# needed to ensure we got an index for an arrayref based generator
if ($con_gen) {
$spec = $con_gen->all_attribute_specs->{$name};
}
$acc_gen->generate_method($target, $name, $spec);
}
}
sub _undefer_subs {
my ($self, $target, $role) = @_;
if ($INC{'Sub/Defer.pm'}) {
Sub::Defer::undefer_package($role);
}
}
sub role_application_steps {
qw(_handle_constructor _undefer_subs _maybe_make_accessors),
$_[0]->SUPER::role_application_steps;
}
sub _build_class_with_roles {
my ($me, $new_name, $superclass, @roles) = @_;
$Moo::MAKERS{$new_name} = {is_class => 1};
$me->SUPER::_build_class_with_roles($new_name, $superclass, @roles);
if ($INC{'Moo/HandleMoose.pm'} && !$Moo::sification::disabled) {
Moo::HandleMoose::inject_fake_metaclass_for($new_name);
}
my $lvl = 0;
my $file;
while ((my $pack, $file) = caller($lvl++)) {
if ($pack ne __PACKAGE__ && $pack ne 'Role::Tiny' && !$pack->isa($me)) {
last;
}
}
_set_loaded($new_name, $file || (caller)[1]);
return $new_name;
}
sub _gen_apply_defaults_for {
my ($me, $class, @roles) = @_;
my @attrs = map @{$INFO{$_}{attributes}||[]}, @roles;
my $con_gen;
my $m;
return undef
unless $INC{'Moo.pm'}
and @attrs
and $con_gen = Moo->_constructor_maker_for($class)
and $m = Moo->_accessor_maker_for($class);
my $specs = $con_gen->all_attribute_specs;
my %seen;
my %captures;
my @set;
while (my ($name, $spec) = splice @attrs, 0, 2) {
next
if $seen{$name}++;
next
unless $m->has_eager_default($name, $spec);
my ($has, $has_cap)
= $m->generate_simple_has('$_[0]', $name, $spec);
my ($set, $pop_cap)
= $m->generate_use_default('$_[0]', $name, $spec, $has);
@captures{keys %$has_cap, keys %$pop_cap}
= (values %$has_cap, values %$pop_cap);
push @set, $set;
}
return undef
if !@set;
my $code = join '', map "($_),", @set;
no warnings 'void';
require Sub::Quote;
return Sub::Quote::quote_sub(
"${class}::_apply_defaults",
$code,
\%captures,
{
package => $class,
no_install => 1,
no_defer => 1,
}
);
}
sub apply_roles_to_object {
my ($me, $object, @roles) = @_;
my $new = $me->SUPER::apply_roles_to_object($object, @roles);
my $class = ref $new;
_set_loaded($class, (caller)[1]);
if (!exists $APPLY_DEFAULTS{$class}) {
$APPLY_DEFAULTS{$class} = $me->_gen_apply_defaults_for($class, @roles);
}
if (my $apply_defaults = $APPLY_DEFAULTS{$class}) {
local $Carp::Internal{+__PACKAGE__} = 1;
local $Carp::Internal{$class} = 1;
$new->$apply_defaults;
}
return $new;
}
sub _install_single_modifier {
my ($me, @args) = @_;
_install_modifier(@args);
}
sub _install_does {
my ($me, $to) = @_;
# If Role::Tiny actually installed the DOES, give it a name
my $new = $me->SUPER::_install_does($to) or return;
return _name_coderef("${to}::DOES", $new);
}
sub does_role {
my ($proto, $role) = @_;
return 1
if Role::Tiny::does_role($proto, $role);
my $meta;
if ($INC{'Moose.pm'}
and $meta = Class::MOP::class_of($proto)
and ref $meta ne 'Moo::HandleMoose::FakeMetaClass'
and $meta->can('does_role')
) {
return $meta->does_role($role);
}
return 0;
}
sub _handle_constructor {
my ($me, $to, $role) = @_;
my $attr_info = $INFO{$role} && $INFO{$role}{attributes};
return unless $attr_info && @$attr_info;
my $info = $INFO{$to};
my $con = $INC{"Moo.pm"} && Moo->_constructor_maker_for($to);
my %existing
= $info ? @{$info->{attributes} || []}
: $con ? %{$con->all_attribute_specs || {}}
: ();
my @attr_info =
map { @{$attr_info}[$_, $_+1] }
grep { ! $existing{$attr_info->[$_]} }
map { 2 * $_ } 0..@$attr_info/2-1;
if ($info) {
push @{$info->{attributes}||=[]}, @attr_info;
}
elsif ($con) {
# shallow copy of the specs since the constructor will assign an index
$con->register_attribute_specs(map ref() ? { %$_ } : $_, @attr_info);
}
}
1;
__END__
=head1 NAME
Moo::Role - Minimal Object Orientation support for Roles
=head1 SYNOPSIS
package My::Role;
use Moo::Role;
use strictures 2;
sub foo { ... }
sub bar { ... }
has baz => (
is => 'ro',
);
1;
And elsewhere:
package Some::Class;
use Moo;
use strictures 2;
# bar gets imported, but not foo
with 'My::Role';
sub foo { ... }
1;
=head1 DESCRIPTION
C<Moo::Role> builds upon L<Role::Tiny>, so look there for most of the
documentation on how this works (in particular, using C<Moo::Role> also
enables L<strict> and L<warnings>). The main addition here is extra bits to
make the roles more "Moosey;" which is to say, it adds L</has>.
=head1 IMPORTED SUBROUTINES
See L<Role::Tiny/IMPORTED SUBROUTINES> for all the other subroutines that are
imported by this module.
=head2 has
has attr => (
is => 'ro',
);
Declares an attribute for the class to be composed into. See
L<Moo/has> for all options.
=head1 CLEANING UP IMPORTS
L<Moo::Role> cleans up its own imported methods and any imports
declared before the C<use Moo::Role> statement automatically.
Anything imported after C<use Moo::Role> will be composed into
consuming packages. A package that consumes this role:
package My::Role::ID;
use Digest::MD5 qw(md5_hex);
use Moo::Role;
use Digest::SHA qw(sha1_hex);
requires 'name';
sub as_md5 { my ($self) = @_; return md5_hex($self->name); }
sub as_sha1 { my ($self) = @_; return sha1_hex($self->name); }
1;
..will now have a C<< $self->sha1_hex() >> method available to it
that probably does not do what you expect. On the other hand, a call
to C<< $self->md5_hex() >> will die with the helpful error message:
C<Can't locate object method "md5_hex">.
See L<Moo/"CLEANING UP IMPORTS"> for more details.
=head1 SUPPORT
See L<Moo> for support and contact information.
=head1 AUTHORS
See L<Moo> for authors.
=head1 COPYRIGHT AND LICENSE
See L<Moo> for the copyright and license.
=cut