type ('a, 'b) resultb = ( 'a, 'b ) Result.t box
val lift : ( 'a -> 'b Lwt.t ) -> 'a -> 'b box
val bind : 'a box -> ( 'a -> 'b Lwt.t ) -> 'b box
val return : 'a -> 'a box
val get : 'a box -> 'a Lwt.t
val (!@) : 'a box -> 'a Lwt.t
val put : 'a Lwt.t -> 'a box
val (~@) : 'a Lwt.t -> 'a box