signature CML_UTIL =
sig
  val apply : ('a -> 'b) -> 'a -> 'b
end;

structure U :> CML_UTIL =
struct
  fun apply f x =
    let
      val result = ref (fn () => raise Match)
      val _ = RunCML.doit
	((fn () => let val r = f x in result := (fn () => r) end),
	 NONE)
    in
      (!result) ()
    end
end;