Internal to Async -- see Deferred for the public API.
include sig ... endval sexp_of_t : ('a ‑> Sexplib.Sexp.t) ‑> 'a t ‑> Sexplib.Sexp.tinclude Core_kernel.Invariant.S1 with type a t := a tval invariant : 'a Base__.Invariant_intf.inv ‑> 'a t Base__.Invariant_intf.invval of_ivar : 'a Async_kernel__.Ivar0.t ‑> 'a tval create : ('a Async_kernel__.Ivar0.t ‑> unit) ‑> 'a tval peek : 'a t ‑> 'a optionval value_exn : 'a t ‑> 'aval is_determined : _ t ‑> boolval return : 'a ‑> 'a tval upon : 'a t ‑> ('a ‑> unit) ‑> unitmodule Handler : sig ... endval add_handler : 'a t ‑> ('a ‑> unit) ‑> Async_kernel.Execution_context.t ‑> 'a Handler.t