package Moose::Exception::MetaclassMustBeDerivedFromClassMOPClass; our $VERSION = '2.2010'; use Moose; extends 'Moose::Exception'; has 'class_name' => ( is => 'ro', isa => 'Str', required => 1 ); sub _build_message { my $self = shift; "The metaclass (".$self->class_name.") must be derived from Class::MOP::Class"; } __PACKAGE__->meta->make_immutable; 1;