The static Atomics
.add()
method adds a given value at a given position in the array and returns the old value at that position. This atomic operation guarantees that no other write happens until the modified value is written back.
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Syntax
Atomics.add(typedArray, index, value)
Parameters
typedArray
- An integer typed array. One of
Int8Array
,Uint8Array
,Int16Array
,Uint16Array
,Int32Array
,Uint32Array
,BigInt64Array
, orBigUint64Array
. index
- The position in the
typedArray
to add avalue
to. value
- The number to add.
Return value
The old value at the given position (typedArray[index]
).
Exceptions
- Throws a
TypeError
, iftypedArray
is not one of the allowed integer types. - Throws a
RangeError
, ifindex
is out of bounds in thetypedArray
.
Examples
Using add()
const sab = new SharedArrayBuffer(1024); const ta = new Uint8Array(sab); Atomics.add(ta, 0, 12); // returns 0, the old value Atomics.load(ta, 0); // 12
Specifications
Specification |
---|
ECMAScript (ECMA-262) The definition of 'Atomics.add' in that specification. |
Browser compatibility
The compatibility table on this page is generated from structured data. If you'd like to contribute to the data, please check out https://github.com/mdn/browser-compat-data and send us a pull request.
Desktop | Mobile | Server | |||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|
add | Chrome
Full support
68
| Edge
Full support
79
| Firefox
Full support
78
| IE No support No | Opera No support No | Safari No support 10.1 — 11.1 | WebView Android
No support
60 — 63
| Chrome Android
No support
60 — 63
| Firefox Android
Full support
57
| Opera Android No support No | Safari iOS No support 10.3 — 11.3 | Samsung Internet Android
No support
No
| nodejs Full support 8.10.0 |
Legend
- Full support
- Full support
- No support
- No support
- See implementation notes.
- See implementation notes.
- User must explicitly enable this feature.
- User must explicitly enable this feature.