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package MooseX::ABC;
use Moose ();
use Moose::Exporter;
use Moose::Util::MetaRole;
sub requires {
my $caller = shift;
my $meta = Class::MOP::class_of($caller);
$meta->add_required_method($_) for @_;
}
Moose::Exporter->setup_import_methods(
with_caller => [qw(requires)],
);
sub init_meta {
shift;
my %options = @_;
Moose->init_meta(%options);
Moose::Util::MetaRole::apply_base_class_roles(
for_class => $options{for_class},
roles => ['MooseX::ABC::Role::Object'],
);
Moose::Util::MetaRole::apply_metaclass_roles(
for_class => $options{for_class},
metaclass_roles => ['MooseX::ABC::Trait::Class'],
);
return Class::MOP::class_of($options{for_class});
}
=for motivation
22:41 <@rjbs> So, say I wanted to write 'shape'
22:41 <@rjbs> as a class
22:41 <@rjbs> but an abstract base class
22:41 <@rjbs> I could say: requires 'area'
22:41 <@rjbs> except I can't, because a class can't be abstract in that sense,
in Perl
22:41 <@rjbs> er, in Moose
22:42 <@rjbs> so to use a delegate is a compromise
22:42 <@rjbs> It isn't what I want: an ABC
22:42 <@rjbs> It isn't entirely what I don't wnat: a role
22:42 <@doy> i wonder if something like a lazy role would work
22:42 <@rjbs> lazy role?
22:42 <@doy> instead of dying if all required methods aren't satisfied at
compile time, do it at instantiation time
22:43 <@doy> applying a role and not satisfying all requires turns that class
into an abstract class
22:43 <@rjbs> but now we're back to instantiation time!
22:43 <@rjbs> I want compile time.
22:44 <@rjbs> package Shape; use Moose::ABC; # now you get no new method, you
can't instantiate directly, and you have "requires" sugar
22:44 <@rjbs> and if you "extends 'Shape'" without fulfilling rqeuires, you die
22:44 <@doy> yeah, that would be nicer
=cut
1;
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