func (be *BinaryMessage) Eval(s *rt.Scope) rt.Value { return rt.SendMessage(be.Receiver, be.Behavior, []rt.Expr{be.Arg}, s) }
func (ke *KeywordMessage) Eval(s *rt.Scope) rt.Value { return rt.SendMessage(ke.Receiver, ke.Behavior, ke.Args, s) }
func (ue *UnaryMessage) Eval(s *rt.Scope) rt.Value { return rt.SendMessage(ue.Receiver, ue.Behavior, []rt.Expr{}, s) }