What is Atomics?
Atomics are used with SharedArrayBuffer(generic fixed-length binary data buffer) objects. Atomics are not constructors like other global objects. Atomics cannot be used with a new operator or can be invoked as a function.
Multiple threads can read and write the same data in memory when there shared memory is. To ensure that predicted values are written and read accurately, another operation cannot start until and unless the current one finishes. Atomic operations also cannot be interrupted.
Among the Atomic Operations, there is a method Atomics.add() that is used to add a given value at a given position in an array and return the old value at that position. No other write operation can happen until the modified value is written back.
Atomics.add(typedArray, index, value)
- typedarray : It is the shared integer typed array you want to modify.
- index : It is the position in the typedArray where you want to add a value.
- value : It is the number you want to add.
Atomics.add() returns the old value at the given position (typedArray[index]).
Examples for the above function are provided below.
Input : arr = 9; Atomics.add(arr, 0, 3); Output : 9 Input : arr = 3; Atomics.add(arr, 0, 2); Output : 3
Codes for the above function are provided below.
- Throws a TypeError, if typedArray is not one of the allowed integer types.
- Throws a TypeError, if typedArray is not a shared typed array type.
- Throws a RangeError, if the index is out of bounds in the typedArray.