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Hofstadter on Lisp (1983)

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372 points Eric_WVGG | 1 comments | 16 Oct 24 13:44 UTC | HN request time: 0.256s | source
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timonoko ◴[17 Oct 24 00:53 UTC] No.41865389[source]▶
Maclisp goodness:

  (compress (reverse (explode x)))
Elisp much improved:

  (defun explode (x)
    (if (symbolp x) (setq x (symbol-name x)))
    (string-to-list x))
  (defun compress (x) (concat x))
replies(3): >>41865620 #>>41865873 #>>41869520 #
1. g19205 ◴[17 Oct 24 13:33 UTC] No.41869520[source]▶
this is how explode behaves on a lisp machine:

    (defun explode (x)
       (mapcar (lambda (x)
          (intern (char-to-string x)))
        (string-to-list (prin1 x))))
turning character into symbol seems natural, because then you are reducing your needed function space even more. I'm surprised the original operated on prin1 output, not sure what the logic behind that is. on a lisp machine (zl:explode "foo") gives me '(|"| |f| |o| |o| |"|)