(module Animal
  (class Duck
    (attr name)
    (initialize (name) (self.name= name))
    (def sleeping self::sleeping)
    (def sleep (self::sleeping= #t))))

(class std::Object
  (def duck? (self.is_a? Duck)))

(-> duck (Duck.new 'Donald))

('(" name sleep sleeping).each' (do (mid)
  (duck.send mid)))

('(" quack walk)'.each (do (mid)
  (duck.define_method mid (do (puts "#{mid}ing...")))))

(duck.quack)
(duck.walk)
(Duck.define_method :is_a_duck??? (do #t))
(-> swissie (Duck.new 'Swissie))
(swissie.is_a_duck???)

(-> += (# (s v)
  (~> args._^.s (+ s v))))

(-> a 1)
(+= a 3) ;a=1+3

(-> a 1)
(a.++) ;... bad..... QAQ (-> a (++ a))
(b::a= 1)
(b::a.++) ; (-> b::a (++ 1)) 虽然好像在这里没有问题（b::a 稍后会被找到，不会使用 OO 语法）
(p b::a)