The Atomics.wait() in JavaScript is an in-built method that is used to verify whether a given position in an Int32Array still contains a given value and if so sleeps, awaiting a wakeup or a timeout. The Atomics.wait() operation returns a string that is either “ok”, “not-equal”, or “timed-out”. The integer typedarray, index, and value are passed as an argument to the function and timeout is also an argument but it is optional.
Syntax:
Atomics.wait(typedArray, index, value, timeout)
Parameters: This method accepts four parameters as mentioned above and described below:
- typedarray: This parameter specifies a shared integer typed array Int16Array.
- index: This parameter specifies the position in the array, typedArray to wait on.
- value: This parameter specifies the expected value to test.
- timeout: This parameter is an optional parameter. It is time to wait in milliseconds.
Return value: The Atomics.wait() method returns the String which is either “ok”, “not-equal”, or “timed-out”.
Examples:
Input: arr[0] = 5
Atomics.wait(arr, 0, 0, 1)
Output: not-equal
Input: arr[0] = 4
Atomics.wait(arr, 1, 0, 1)
Output: time-out
The below programs illustrate Atomics.wait() method in JavaScript:
Example 1: This program illustrates the basic use of the Atomics.wait() method in JavaScript.
javascript
let buf = new SharedArrayBuffer(1024); let arr = new Int32Array(buf); arr[0] = 5; console.log(Atomics.load(arr, 0)); console.log(Atomics.and(arr, 0, 9)); console.log(Atomics.wait(arr, 0, 0, 1)); console.log(Atomics.load(arr, 0)); |
Output:
5 5 not-equal 1
Example 2: This program illustrates the basic use of Atomics.wait() method in JavaScript.
javascript
let buf = new SharedArrayBuffer(1024); let arr = new Int32Array(buf); arr[0] = 5; console.log(Atomics.load(arr, 0)); console.log(Atomics.and(arr, 0, 9)); console.log(Atomics.wait(arr, 1, 0, 1)); console.log(Atomics.load(arr, 0)); |
Output:
5 5 time-out 1
Exceptions:
- If the typedArray is not a shared Int32Array then the Atomics.wait() operation throws a TypeError.
- If the index is used as an argument to the Atomics.wait() operation is out of the bound in the typedArray then the Atomics.store( ) operation throws a RangeError
We have a complete list of Javascript Atomics methods, to check those please go through the Javascript Atomics Complete Reference article.
Supported Browser:
- Google Chrome
- Microsoft Edge
- Firefox
