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Grzegorz Kućmierz
Grzegorz Kućmierz

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What is the JavaScript version of sleep()?

#sleep #async #await #javascript

There is no sleep function in JavaScript, but with async/await syntax it is very easy to implement.

If we need to mimic behavior like this written in c code.

#include<stdio.h>  main() { printf("Sleeping for 1 second.\n"); sleep(1); return 0; }
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Using async/await syntax it is very simple.

const sleep = (timeout = 1) => new Promise((resolve) => { setTimeout(resolve, timeout * 1e3); }); console.log('before sleep'); await sleep(1); console.log('after 1 second!');
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You can also use milliseconds version.

const sleepMs = (timeout = 1e3) => new Promise((resolve) => { setTimeout(resolve, timeout); }); console.log('before sleep'); await sleep(1000); console.log('after 1000 milliseconds!');
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