SteveGilham

let rec ( ^* ) (generator: ('x option -> continuation) -> continuation, test)
            (consumer: 'x list -> 'x option -> continuation) =
    generator (function Some x -> if test x
                                  then (generator, test) ^* (fun l -> consumer(x::l))
                                  else consumer [] (Some x)
                      | None -> consumer [] None);;

SteveGilham

type LispLex = Bra | Ket | Dot | Str of string | Num of int | Symbol of string
let alpha c = ((c >= 'a') && (c <= 'z')) || ((c >= 'A') && (c <= 'Z'))
let digit c = (c >= '0') && (c <= '9')
let eqChar c c' = c = c'
let l2s l = String(List.toArray l)
let ( ^| ) p q = fun x -> (p x) || (q x)

// Read a symbol from the input
let readSymbol s char g =
     (lexGetChar s, alpha ^| digit ^| eqChar '_') ^*

SteveGilham

type continuation = K of (unit -> unit)
step1: continuation -> continuation
end: continuation
program = step1 end : continuation

SteveGilham

Return: t -> M t
Fail: M t
Bind: (t1 -> M t2) -> M t1 -> M t2

SteveGilham

m >>= fun value1 ->
E1[value1] >>= fun value2 ->
E2[value2]

SteveGilham

value1 := m;
value2 := E1[value1]
E2[value2]

SteveGilham

let __binder__<'T, 'U, 'M when 'M : (static member bind : ('T -> 'U 'M ) -> 'T 'M -> 'U 'M)> (x: 'T 'M) (f : 'T -> 'U 'M) =
    x |> 'M.bind f;;
let (>>=) = __binder__;;

SteveGilham

let (>>) m1 m2 = m1 >>= fun () -> m2;;

SteveGilham

let Apply m1 m2
    = m1 >>= fun f ->
      m2 >>= fun x ->
      Return (f x);;

SteveGilham

let Lift f m =
    m >>= fun x ->
    Return (f x);;