package Moo::Role;
use strictures 1;
use Moo::_Utils;
use base qw(Role::Tiny);
require Moo::sification;
BEGIN { *INFO = \%Role::Tiny::INFO }
our %INFO;
sub _install_tracked {
my ($target, $name, $code) = @_;
$INFO{$target}{exports}{$name} = $code;
_install_coderef "${target}::${name}" => "Moo::Role::${name}" => $code;
}
sub import {
my $target = caller;
my ($me) = @_;
strictures->import;
if ($Moo::MAKERS{$target} and $Moo::MAKERS{$target}{is_class}) {
die "Cannot import Moo::Role into a Moo class";
}
$INFO{$target} ||= {};
# get symbol table reference
my $stash = do { no strict 'refs'; \%{"${target}::"} };
_install_tracked $target => has => sub {
my ($name_proto, %spec) = @_;
my $name_isref = ref $name_proto eq 'ARRAY';
foreach my $name ($name_isref ? @$name_proto : $name_proto) {
my $spec_ref = $name_isref ? +{%spec} : \%spec;
($INFO{$target}{accessor_maker} ||= do {
require Method::Generate::Accessor;
Method::Generate::Accessor->new
})->generate_method($target, $name, $spec_ref);
push @{$INFO{$target}{attributes}||=[]}, $name, $spec_ref;
$me->_maybe_reset_handlemoose($target);
}
};
# install before/after/around subs
foreach my $type (qw(before after around)) {
_install_tracked $target => $type => sub {
require Class::Method::Modifiers;
push @{$INFO{$target}{modifiers}||=[]}, [ $type => @_ ];
$me->_maybe_reset_handlemoose($target);
};
}
_install_tracked $target => requires => sub {
push @{$INFO{$target}{requires}||=[]}, @_;
$me->_maybe_reset_handlemoose($target);
};
_install_tracked $target => with => sub {
$me->apply_roles_to_package($target, @_);
$me->_maybe_reset_handlemoose($target);
};
return if $INFO{$target}{is_role}; # already exported into this package
$INFO{$target}{is_role} = 1;
*{_getglob("${target}::meta")} = $me->can('meta');
# grab all *non-constant* (stash slot is not a scalarref) subs present
# in the symbol table and store their refaddrs (no need to forcibly
# inflate constant subs into real subs) - also add '' to here (this
# is used later) with a map to the coderefs in case of copying or re-use
my @not_methods = ('', map { *$_{CODE}||() } grep !ref($_), values %$stash);
@{$INFO{$target}{not_methods}={}}{@not_methods} = @not_methods;
# a role does itself
$Role::Tiny::APPLIED_TO{$target} = { $target => undef };
if ($INC{'Moo/HandleMoose.pm'}) {
Moo::HandleMoose::inject_fake_metaclass_for($target);
}
}
# duplicate from Moo::Object
sub meta {
require Moo::HandleMoose::FakeMetaClass;
my $class = ref($_[0])||$_[0];
bless({ name => $class }, 'Moo::HandleMoose::FakeMetaClass');
}
sub unimport {
my $target = caller;
_unimport_coderefs($target, $INFO{$target});
}
sub _maybe_reset_handlemoose {
my ($class, $target) = @_;
if ($INC{"Moo/HandleMoose.pm"}) {
Moo::HandleMoose::maybe_reinject_fake_metaclass_for($target);
}
}
sub _inhale_if_moose {
my ($self, $role) = @_;
_load_module($role);
my $meta;
if (!$INFO{$role}
and (
$INC{"Moose.pm"}
and $meta = Class::MOP::class_of($role)
)
or (
Mouse::Util->can('find_meta')
and $meta = Mouse::Util::find_meta($role)
)
) {
$INFO{$role}{methods} = {
map +($_ => $role->can($_)),
grep !$meta->get_method($_)->isa('Class::MOP::Method::Meta'),
$meta->get_method_list
};
$Role::Tiny::APPLIED_TO{$role} = {
map +($_->name => 1), $meta->calculate_all_roles
};
$INFO{$role}{requires} = [ $meta->get_required_method_list ];
$INFO{$role}{attributes} = [
map +($_ => do {
my $spec = { %{$meta->get_attribute($_)} };
if ($spec->{isa}) {
my $get_constraint = do {
my $pkg = $meta->isa('Mouse::Meta::Role')
? 'Mouse::Util::TypeConstraints'
: 'Moose::Util::TypeConstraints';
_load_module($pkg);
$pkg->can('find_or_create_isa_type_constraint');
};
my $tc = $get_constraint->($spec->{isa});
my $check = $tc->_compiled_type_constraint;
$spec->{isa} = sub {
&$check or die "Type constraint failed for $_[0]"
};
if ($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 => $mod ];
}
}
}
require Class::Method::Modifiers if @$mods;
$INFO{$role}{inhaled_from_moose} = 1;
}
}
sub _maybe_make_accessors {
my ($self, $role, $target) = @_;
my $m;
if ($INFO{$role}{inhaled_from_moose}
or $INC{"Moo.pm"}
and $m = Moo->_accessor_maker_for($target)
and ref($m) ne 'Method::Generate::Accessor') {
$self->_make_accessors($role, $target);
}
}
sub _make_accessors_if_moose {
my ($self, $role, $target) = @_;
if ($INFO{$role}{inhaled_from_moose}) {
$self->_make_accessors($role, $target);
}
}
sub _make_accessors {
my ($self, $role, $target) = @_;
my $acc_gen = ($Moo::MAKERS{$target}{accessor} ||= do {
require Method::Generate::Accessor;
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, $spec);
}
}
sub apply_roles_to_package {
my ($me, $to, @roles) = @_;
foreach my $role (@roles) {
$me->_inhale_if_moose($role);
}
$me->SUPER::apply_roles_to_package($to, @roles);
}
sub apply_single_role_to_package {
my ($me, $to, $role) = @_;
$me->_inhale_if_moose($role);
$me->_handle_constructor($to, $INFO{$role}{attributes});
$me->_maybe_make_accessors($role, $to);
$me->SUPER::apply_single_role_to_package($to, $role);
}
sub create_class_with_roles {
my ($me, $superclass, @roles) = @_;
my $new_name = join(
'__WITH__', $superclass, my $compose_name = join '__AND__', @roles
);
return $new_name if $Role::Tiny::COMPOSED{class}{$new_name};
foreach my $role (@roles) {
$me->_inhale_if_moose($role);
}
my $m;
if ($INC{"Moo.pm"}
and $m = Moo->_accessor_maker_for($superclass)
and ref($m) ne 'Method::Generate::Accessor') {
# old fashioned way time.
*{_getglob("${new_name}::ISA")} = [ $superclass ];
$me->apply_roles_to_package($new_name, @roles);
return $new_name;
}
require Sub::Quote;
$me->SUPER::create_class_with_roles($superclass, @roles);
foreach my $role (@roles) {
die "${role} is not a Role::Tiny" unless my $info = $INFO{$role};
}
$Moo::MAKERS{$new_name} = {};
$me->_handle_constructor(
$new_name, [ map @{$INFO{$_}{attributes}||[]}, @roles ], $superclass
);
return $new_name;
}
sub _composable_package_for {
my ($self, $role) = @_;
my $composed_name = 'Role::Tiny::_COMPOSABLE::'.$role;
return $composed_name if $Role::Tiny::COMPOSED{role}{$composed_name};
$self->_make_accessors_if_moose($role, $composed_name);
$self->SUPER::_composable_package_for($role);
}
sub _install_single_modifier {
my ($me, @args) = @_;
_install_modifier(@args);
}
sub _handle_constructor {
my ($me, $to, $attr_info, $superclass) = @_;
return unless $attr_info && @$attr_info;
if ($INFO{$to}) {
push @{$INFO{$to}{attributes}||=[]}, @$attr_info;
} else {
# only fiddle with the constructor if the target is a Moo class
if ($INC{"Moo.pm"}
and my $con = Moo->_constructor_maker_for($to, $superclass)) {
# shallow copy of the specs since the constructor will assign an index
$con->register_attribute_specs(map ref() ? { %$_ } : $_, @$attr_info);
}
}
}
1;
=head1 NAME
Moo::Role - Minimal Object Orientation support for Roles
=head1 SYNOPSIS
package My::Role;
use Moo::Role;
sub foo { ... }
sub bar { ... }
has baz => (
is => 'ro',
);
1;
And elsewhere:
package Some::Class;
use Moo;
# 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. 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 SUPPORT
See L<Moo> for support and contact informations.
=head1 AUTHORS
See L<Moo> for authors.
=head1 COPYRIGHT AND LICENSE
See L<Moo> for the copyright and license.