extra/nested-comments/nested-comments.factor

   1 ! Copyright (C) 2009 blei, Doug Coleman.
   2 ! See http://factorcode.org/license.txt for BSD license.
   3 USING: kernel locals make math multiline sequences ;
   4 IN: nested-comments
   5
   6 : (count-subsequences) ( count substring string n -- count' )
   7     [ 2dup ] dip start* [
   8         pick length +
   9         [ 1 + ] 3dip (count-subsequences)
  10     ] [
  11         2drop
  12     ] if* ;
  13
  14 : count-subsequences ( subseq seq -- n )
  15     [ 0 ] 2dip 0 (count-subsequences) ;
  16
  17 : parse-nestable-comment ( parsed-vector left-to-parse -- parsed-vector )
  18     1 - "*)" parse-multiline-string
  19     [ "(*" ] dip
  20     count-subsequences + dup 0 > [ parse-nestable-comment ] [ drop ] if ;
  21
  22 SYNTAX: (* 1 parse-nestable-comment ;