Moose type constraints are not strings, they are instances of Moose::Meta::TypeConstraint.
Sure, I assumed they have semantics beyond 'being a String'. I just meant from the syntactic perspective,
Moose::Manual::Types pretty much makes it look like the types are strings. At least
...
isa => Str | ArrayRef,
...
doesn't work without MooseX::Types (Bareword "Str" not allowed while "strict subs"...)
Anyway, I tried to make this inherited union constraints "do what I mean" for multiple inheritance and came up with
package ValAtom;
use strict;
use warnings;
use 5.10.1;
use Moose;
use MooseX::Types::Moose -all;
extends 'KeyAtom', 'JustTesting';
has '+data' => (
isa => __PACKAGE__->_existing_constraint('data') . ' | ArrayRe
+f | HashRef',
);
sub _existing_constraint {
my ($class, $attr) = @_;
return join ' | ', map {
$_->meta->find_attribute_by_name($attr)->type_constraint
} $class->meta->superclasses;
}
1;
Back to string again - obviously - as I couldn't figure out how to do it otherwise. But this seems to work.