Bounded_queue.RecvReceiving side
type 'a t = {on_non_empty : (unit -> unit) -> unit;on_non_empty f registers f to be called whenever the queue transitions from empty to non-empty.
try_pop : unit -> 'a pop_result;Try to pop an item right now.
*)common : Common.t;}val try_pop : 'a t -> 'a pop_resultval on_non_empty : 'a t -> (unit -> unit) -> unitval closed : 'a t -> boolval num_discarded : 'a t -> intval size : 'a t -> intval high_watermark : 'a t -> int