From: jj3000
Subject: function that split a list
Date: Thu, 14 Oct 1999 00:00:00 +0000
Message-ID: <7u4p0m$ld5$1@nnrp1.deja.com>

I'm stuck trying to write a function that will split a list in multiple
lists..  e.g. (splitlist '( A B C D E))
suppose C is a delimiter atom that I pick, the result should be three
lists (A B) (C) (D E)

I know this is probably very trival, but I'm just started learning
lisp. Can someone please show me how to do this properly.

Thanks


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From: Barry Margolin
Subject: Re: function that split a list
Date: Thu, 14 Oct 1999 00:00:00 +0000
Message-ID: <JwmN3.854$854.35050@burlma1-snr2>

In article <············@nnrp1.deja.com>,
jj3000  <·········@my-deja.com> wrote:
>I'm stuck trying to write a function that will split a list in multiple
>lists..  e.g. (splitlist '( A B C D E))
>suppose C is a delimiter atom that I pick, the result should be three
>lists (A B) (C) (D E)
>
>I know this is probably very trival, but I'm just started learning
>lisp. Can someone please show me how to do this properly.

(defun splitlist (delimiter list)
  (let ((pos (position delimiter list)))
    (when pos
      (list (subseq list 0 pos) (list delimiter)
            (subseq list (1+ pos))))))

(defun splitlist (delimiter list)
  (let ((tail (member delimiter list)))
    (when tail
      (list (ldiff list tail)
            (list delimiter)
            (cdr tail)))))

-- 
Barry Margolin, ······@bbnplanet.com
GTE Internetworking, Powered by BBN, Burlington, MA
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