Module GenM_intf

module GenM_intf: sig .. end
A value of type 'a t is an iterator over values of type 'a that live in the monad M.t. For instance, if M is Lwt, accessing each element might require some IO operation (reading a file, etc.)

type 'a gen = unit -> 'a option 
module type MONAD = sig .. end
module type S = sig .. end