How to Slow Down a Loop in JavaScript

In JavaScript, when you need to call an API multiple times within a loop, it’s important to consider rate limiting and the impact of making too many requests in a short period of time. To address this issue, you can slow down the loop by implementing a sleep function.

To set up the sleep function, you can use the following code:

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const sleep = (milliseconds) => {
  return new Promise(resolve => setTimeout(resolve, milliseconds));
}

Once you have the sleep function in place, you can use it within your loop to pause the execution for a specified duration. For example, if you want to pause for 1 second in each iteration, you can use the following code:

const list = [1, 2, 3, 4];
const doSomething = async () => {
  for (const item of list) {
    await sleep(1000);
    console.log('🦄');
  }
}

doSomething();

By utilizing the sleep function with the await keyword, the loop will pause for the specified duration before moving on to the next iteration. This effectively slows down the loop and allows you to control the rate at which API calls are made.

Tags: JavaScript, loop, API, rate limiting, sleep function