regression/char.scan.sml

   1 val dquote = "\""
   2
   3 val _ = print (concat [Bool.toString (isSome (Char.fromString dquote)), "\n"])
   4
   5 val scan: string -> unit =
   6    fn s =>
   7    let
   8       val n = String.size s
   9       fun reader i =
  10          if i = n
  11             then NONE
  12          else SOME (String.sub (s, i), i + 1)
  13    in
  14       case Char.scan reader 0 of
  15          NONE => print "NONE\n"
  16        | SOME (c, i) => print (concat [str c, " at ", Int.toString i,
  17                                        " of ", Int.toString n, "\n"])
  18    end
  19
  20 val _ =
  21    List.app scan ["a\\ \\", "\\ \\a", "\\ \\a\\ \\", "\\ \\\\ \\a",
  22                   "\\ \\"]