async_kernel v0.11.1 · OCaml Package

A write-once cell that can be empty or full (i.e., hold a single value).

One can read an ivar to obtain a deferred that becomes determined when the ivar is filled. An ivar is similar to an 'a option ref, except it is an error to fill an already full ivar.

type 'a t

val bin_t : 
  'a Core_kernel.Bin_prot.Type_class.t ->
  'a t Core_kernel.Bin_prot.Type_class.t

val bin_read_t : 
  'a Core_kernel.Bin_prot.Read.reader ->
  'a t Core_kernel.Bin_prot.Read.reader

val __bin_read_t__ : 
  'a Core_kernel.Bin_prot.Read.reader ->
  (int -> 'a t) Core_kernel.Bin_prot.Read.reader

val bin_reader_t : 
  'a Core_kernel.Bin_prot.Type_class.reader ->
  'a t Core_kernel.Bin_prot.Type_class.reader

val bin_size_t : 
  'a Core_kernel.Bin_prot.Size.sizer ->
  'a t Core_kernel.Bin_prot.Size.sizer

val bin_write_t : 
  'a Core_kernel.Bin_prot.Write.writer ->
  'a t Core_kernel.Bin_prot.Write.writer

val bin_writer_t : 
  'a Core_kernel.Bin_prot.Type_class.writer ->
  'a t Core_kernel.Bin_prot.Type_class.writer

val bin_shape_t : Core_kernel.Bin_prot.Shape.t -> Core_kernel.Bin_prot.Shape.t

val sexp_of_t : 
  ('a -> Ppx_sexp_conv_lib.Sexp.t) ->
  'a t ->
  Ppx_sexp_conv_lib.Sexp.t

type 'a ivar = 'a t

include Core_kernel.Invariant.S1 with type 'a t := 'a t

val invariant : ('a -> unit) -> 'a t -> unit

val equal : 'a t -> 'a t -> bool

equal t t' is physical equality of t and t'.

val create : unit -> 'a t

create () returns an empty ivar.

val create_full : 'a -> 'a t

create_full v returns an ivar filled with v.

val fill : 'a t -> 'a -> unit

fill t v fills t with value v if t was empty. If t was full, fill raises an exception. It is guaranteed that immediately after calling fill t, is_some (Deferred.peek (read t)).

val fill_if_empty : 'a t -> 'a -> unit

fill_if_empty t v fills t with v if t is currently empty. If t is full, then fill_if_empty does nothing.

val is_empty : 'a t -> bool

is_empty t returns true if t is empty.

val is_full : 'a t -> bool

is_full t returns true if t is full.

val read : 'a t -> 'a Async_kernel__.Types.Deferred.t

read t returns a deferred that becomes enabled with value v after the ivar is filled with v.

val peek : 'a t -> 'a option

peek t returns Some v iff t is full with value v.

val value_exn : 'a t -> 'a

value_exn t returns v if t is full with value v, and raises otherwise.

val has_handlers : _ t -> bool

has_handlers t returns true if t has handlers waiting on read t.

package async_kernel