How to pause function until value change?

Asked Nov 19 '20 at 08:20

Active Nov 19 '20 at 08:28

Viewed 30 times

I am trying to pause the execution of the function until the value of the global variable changes. But it doesn't work, after waiting, the function did not continue its work. Where is mistake?

let currentFunction = 1;

const sleep = () => {
    currentFunction += 1;
    console.log(currentFunction);
    return new Promise((resolve) => {
        if (currentFunction === 5) {
            return resolve();
        }
        return setTimeout(sleep, 1000);

    });
};

const first = async () => {
    console.log('Hello');
    await sleep();
    console.log('now here');
};

first();

edited Nov 19 '20 at 08:28

Barmar

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asked Nov 19 '20 at 08:20

Слава Иванов

2

You're only resolving the last promise, not the promise created by the original call to `sleep()` – Barmar Nov 19 '20 at 08:26
1

@Barmar, Thanks, I assumed it. You have no idea how I can do it correctly? – Слава Иванов Nov 19 '20 at 08:31
1

Use a loop instead of recursion – Thomas Sablik Nov 19 '20 at 08:31
@ThomasSablik Can you show it in an answer? `setTimeout()` doesn't return a promise, so you can't `await` it in a loop. – Barmar Nov 19 '20 at 08:36
1

You could use `setInterval` instead of `setTimeout`: https://repl.it/@ShashSinha/CumbersomeDimgreyAutoexec#index.js – Sash Sinha Nov 19 '20 at 08:42
1

You can write your own "setTimeout" function that returns a promise. https://wandbox.org/permlink/byuHc68q1PoiO3SF – Thomas Sablik Nov 19 '20 at 08:45
Gentlemen, thank you very much for your help – Слава Иванов Nov 19 '20 at 08:48

How to pause function until value change?

0 Answers0