lib/mlton/basic/option.sig

   1 (* Copyright (C) 1999-2005 Henry Cejtin, Matthew Fluet, Suresh
   2  *    Jagannathan, and Stephen Weeks.
   3  *
   4  * MLton is released under a BSD-style license.
   5  * See the file MLton-LICENSE for details.
   6  *)
   7
   8 signature OPTION =
   9    sig
  10       type 'a t = 'a option
  11
  12       val app: 'a t * ('a -> unit) -> unit
  13       val equals: 'a t * 'a t * ('a * 'a -> bool) -> bool
  14       val exists: 'a t * ('a -> bool) -> bool
  15       val fold: 'a t * 'b * ('a * 'b -> 'b) -> 'b
  16       val forall: 'a t * ('a -> bool) -> bool
  17       val foreach: 'a t * ('a -> unit) -> unit
  18       val isNone: 'a t -> bool
  19       val isSome: 'a t -> bool
  20       val layout: ('a -> Layout.t) -> 'a t -> Layout.t
  21       val map: 'a t * ('a -> 'b) -> 'b t
  22       val toString: ('a -> string) -> 'a t -> string
  23       val valOf: 'a t -> 'a
  24    end