a3/code/Generics/GenPrint.dcl

   1 definition module GenPrint
   2
   3 import StdGeneric
   4
   5 class PrintOutput s where
   6         printOutput :: Char *s -> *s
   7
   8 :: *StringOutput
   9
  10 :: PrintState s
  11
  12 mkPrintState :: *s -> PrintState *s | PrintOutput s
  13 mkStringPrintState :: PrintState StringOutput
  14 printToString :: a -> String | gPrint{|*|} a
  15
  16 (<<-) infixl 0 :: (PrintState *s) a -> *(PrintState *s)
  17         | gPrint{|*|} a & PrintOutput s
  18
  19
  20 instance PrintOutput StringOutput
  21 instance PrintOutput File
  22
  23 generic gPrint a :: a (PrintState *s) -> (PrintState *s) | PrintOutput s
  24
  25 derive gPrint Int, Real, Char, Bool, String, UNIT, PAIR, EITHER, FIELD, CONS, OBJECT, [], {!}, {}
  26 //derive bimap PrintState
  27