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Wikipedia Haiku

botsin.space

1–8 of 8 posts

Re: Wikipedia Haiku

#8
Could a haiku be written for Lisp?

Wow, yes; turns out we can write a working map function in TXR Lisp as a haiku:

  (defun map (f x)
    (if (null x)
      nil 
      (cons [f (car x)] (map f (cdr x)))))
I.e.

  (defun map (f x)
    (if (null x) nil (cons [f (car
                                   x)] (map f (cdr x)))))

i.e.

  de-fun map eff ex
  if null ex nil cons f car
  ex map eff k'dr ex

Comprehensive regression test suite:

  4> [map succ nil]
  nil
  5> [map succ '(1 2 3)]
  (2 3 4)