Module Ivar

module Ivar: sig .. end

An ivar is a write-once cell that can be empty or full (i.e. hold a single value) that one can read and 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

type 'a ivar = 'a t

include Invariant.S1

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 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

module Deferred: sig .. end

The Deferred module exposed here is for async's internal use only.

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

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

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

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

val bin_read_t : 'a Bin_prot.Unsafe_read_c.reader ->
       'a t Bin_prot.Read_ml.reader

val bin_read_t_ : 'a Bin_prot.Unsafe_read_c.reader ->
       'a t Bin_prot.Unsafe_read_c.reader

val bin_read_t__ : 'a Bin_prot.Unsafe_read_c.reader ->
       (int -> 'a t) Bin_prot.Unsafe_read_c.reader

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

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

val bin_write_t : 'a Bin_prot.Unsafe_write_c.writer ->
       'a t Bin_prot.Write_ml.writer

val bin_write_t_ : 'a Bin_prot.Unsafe_write_c.writer ->
       'a t Bin_prot.Unsafe_write_c.writer

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

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

create () returns an empty ivar.

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)).

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

is_empty t returns true if t is empty

is_full t returns true if t is full

The Deferred module exposed here is for async's internal use only.

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