#lang racket
(require [only-in plait test test/exn error print-only-errors])

(define (msg obj selector . args)
  (apply (obj selector) args))

(define o-self-no!
  (lambda (m)
    (case m
      [(first) (lambda (self x) ((self 'second) self (+ x 1)))]
      [(second) (lambda (self x) (+ x 1))])))
(test (msg o-self-no! 'first o-self-no! 5) 7)