#!perl package Point; use Mouse; has 'x' => (isa => 'Int', is => 'rw', required => 1); has 'y' => (isa => 'Int', is => 'rw', required => 1); sub clear { my $self = shift; $self->x(0); $self->y(0); } package Point3D; use Mouse; extends 'Point'; has 'z' => (isa => 'Int', is => 'rw', required => 1); after 'clear' => sub { my $self = shift; $self->z(0); }; package main; # hash or hashrefs are ok for the constructor my $point1 = Point->new(x => 5, y => 7); my $point2 = Point->new({x => 5, y => 7}); my $point3d = Point3D->new(x => 5, y => 42, z => -5); print "point1: ", $point1->dump(); print "point2: ", $point2->dump(); print "point3: ", $point3d->dump(); print "point3d->clear()\n"; $point3d->clear(); print "point3: ", $point3d->dump();