#!/usr/bin/perl; use Moose; use Moose::Util::TypeConstraints; use DateTime; use Test::More tests => 1; subtype 'DateTime', => as 'Object', => where { $_->isa('DateTime') }; has 'datetime' => (is => 'ro', isa => 'DateTime', required => 1); my $type = find_type_constraint('DateTime'); ok( $type, 'made a DateTime constraint' ); done_testing();