Penguin Class

:Class Penguin: Animal,BirdBehaviour,FishBehaviour
    ∇ R←NoCanFly
      :Implements Method BirdBehaviour.Fly
      R←'Although I am a bird, I cannot fly'
    ∇
    ∇ R←LayOneEgg
      :Implements Method BirdBehaviour.Lay
      R←'I lay one egg every year'
    ∇
    ∇ R←Croak
      :Implements Method BirdBehaviour.Sing
      R←'Croak, Croak!'
    ∇
    ∇ R←Dive
      :Implements Method FishBehaviour.Swim
      R←'I can dive and swim like a fish'
    ∇
:EndClass ⍝ Penguin