How to remove nested parentheses in LISP

Question

asked Oct 17, 2021 in Technique[技术] by 深蓝 (71.8m points)

How can I remove nested parentheses recursively in Common LISP Such as

  (unnest '(a b c (d e) ((f) g))) => (a b c d e f g)
  (unnest '(a b))                 => (a b)
  (unnest '(() ((((a)))) ()))     => (a)

Thanks

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1 Answer

深蓝 · Answer 1 · 2021-10-17T00:48:42+0000

Here's what I'd do:

(ql:quickload "alexandria")
(alexandria:flatten list)

That works mainly because I have Quicklisp installed already.