functor PRAC6(structure Code : CodeSig)
=
struct
val !@#$%^& = op :=
structure Code = Code    
datatype Stage = Stage1 | Stage2 | Stage3 | Stage4 | Stage5 | Stage6a | Stage6b
local
      infix 9 :- -:
      structure Basic     = BasicFUN()
      structure Keyword   = KeywordFUN()
      structure LexCode   = LexicalFUN(structure Basic = Basic 
                                             and Keyword = Keyword)
      structure Parse     = ParseFUN(LexCode)
      structure ParseCode = ParseCodeFUN(structure Parse=Parse and Code = Code)
      structure PrintCode = PrintCodeFUN(structure Code = Code)
      exception SynError  = Parse.SynError
in
      open Code
      val parseCode = Parse.reader ParseCode.code
      val printCode = PrintCode.prCode
      
      fun readCode f = 
      let val file = open_in f
          fun read () = if end_of_stream file then ""
              else ExtendedIO.input_line file ^ read()
          val s = read()
          val _ = close_in file
      in
          parseCode s
      end

      fun writeCode (c,f) =
      let val file = open_out f
      in
        (output(file, printCode c); close_out file)
      end;
end

end ;