contrib/sb-bsd-sockets/split.lisp

   1 (in-package :sb-bsd-sockets)
   2
   3 ;;; This courtesy of Pierre Mai in comp.lang.lisp 08 Jan 1999 00:51:44 +0100
   4 ;;; Message-ID: <87lnjebq0f.fsf@orion.dent.isdn.cs.tu-berlin.de>
   5
   6 (defun split (string &optional max (ws '(#\Space #\Tab)))
   7   "Split `string' along whitespace as defined by the sequence `ws'.
   8 The whitespace is elided from the result.  The whole string will be
   9 split, unless `max' is a non-negative integer, in which case the
  10 string will be split into `max' tokens at most, the last one
  11 containing the whole rest of the given `string', if any."
  12   (flet ((is-ws (char) (find char ws)))
  13     (loop for start = (position-if-not #'is-ws string)
  14           then (position-if-not #'is-ws string :start index)
  15           for index = (and start
  16                            (if (and max (= (1+ word-count) max))
  17                                nil
  18                              (position-if #'is-ws string :start start)))
  19           while start
  20           collect (subseq string start index)
  21           count 1 into word-count
  22           while index)))
  23