Atomics.sub()

The static Atomics.sub() method substracts 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.sub(typedArray, index, value)

Parameters

typedArray

An integer typed array. One of Int8Array, Uint8Array, Int16Array, Uint16Array, Int32Array, Uint32Array, BigInt64Array, or BigUint64Array.

index

The position in the typedArray to subtract a value from.

value

The number to subtract.

Return value

The old value at the given position (typedArray[index]).

Exceptions

• Throws a TypeError, if typedArray is not one of the allowed integer types.
• Throws a RangeError, if index is out of bounds in the typedArray.

Examples

Using sub

const sab = new SharedArrayBuffer(1024);
const ta = new Uint8Array(sab);
ta[0] = 48;

Atomics.sub(ta, 0, 12); // returns 48, the old value
Atomics.load(ta, 0); // 36

Specifications

Browser compatibility

See also

• Atomics
• Atomics.add()