fp2/week2/ReturnEnBind.icl

   1 module ReturnEnBind
   2
   3 import StdEnv, Random
   4
   5 Start = 42
   6
   7 (bind1) infix 0 :: (St s a) (a -> (St s b)) -> St s b
   8 //(bind1) infix 0 :: (s -> *(a,s)) (a -> (a -> *(a,s))) -> (s -> *(b,s))
   9 (bind1) f1 f2 = \st0 f2 (fst (f1 st0) (snd (f1 st0))
  10 //      (r, st1) = f1 st0
  11 //(bind) f f2 :== \st0 -> let (r,st1) = f st0
  12 //       in f2 r st1
  13
  14
  15 som2 :: (RandomSeed -> (Int,RandomSeed))
  16 som2 ...
  17
  18 seqList1 :: [St s a] -> St s [a]
  19 seqList1 ...