.TH "Atomic" 3o 2023-09-20 OCamldoc "OCaml library"
.SH NAME
Atomic \- This module provides a purely sequential implementation of the concurrent atomic references provided by the Multicore OCaml standard library:
.SH Module
Module   Atomic
.SH Documentation
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Module
.BI "Atomic"
 : 
.B sig end

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This module provides a purely sequential implementation of the
concurrent atomic references provided by the Multicore OCaml
standard library:
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https://github\&.com/ocaml\-multicore/ocaml\-multicore/blob/parallel_minor_gc/stdlib/atomic\&.mli
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This sequential implementation is provided in the interest of
compatibility: when people will start writing code to run on
Multicore, it would be nice if their use of Atomic was
backward\-compatible with older versions of OCaml without having to
import additional compatibility layers\&.

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.B "Since"
4.12

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.I type 
.B 'a
.I t 

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An atomic (mutable) reference to a value of type 
.ft B
\&'a
.ft R
\&.

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.I val make 
: 
.B 'a -> 'a t
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Create an atomic reference\&.

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.I val get 
: 
.B 'a t -> 'a
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Get the current value of the atomic reference\&.

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.I val set 
: 
.B 'a t -> 'a -> unit
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Set a new value for the atomic reference\&.

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.I val exchange 
: 
.B 'a t -> 'a -> 'a
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Set a new value for the atomic reference, and return the current value\&.

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.I val compare_and_set 
: 
.B 'a t -> 'a -> 'a -> bool
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.ft B
compare_and_set r seen v
.ft R
sets the new value of 
.ft B
r
.ft R
to 
.ft B
v
.ft R
only
if its current value is physically equal to 
.ft B
seen
.ft R
\-\- the
comparison and the set occur atomically\&. Returns 
.ft B
true
.ft R
if the
comparison succeeded (so the set happened) and 
.ft B
false
.ft R
otherwise\&.

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.I val fetch_and_add 
: 
.B int t -> int -> int
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.ft B
fetch_and_add r n
.ft R
atomically increments the value of 
.ft B
r
.ft R
by 
.ft B
n
.ft R
,
and returns the current value (before the increment)\&.

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.I val incr 
: 
.B int t -> unit
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.ft B
incr r
.ft R
atomically increments the value of 
.ft B
r
.ft R
by 
.ft B
1
.ft R
\&.

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.I val decr 
: 
.B int t -> unit
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.ft B
decr r
.ft R
atomically decrements the value of 
.ft B
r
.ft R
by 
.ft B
1
.ft R
\&.

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