Handling Promises when a function returns a value asynchronously

Other Questions JavaScript
,
1

In JavaScript, managing asynchronous operations often involves using Promises, especially when a function needs to return a value after a delay. Essentially, Promises serve as placeholders for values that may not be available immediately. By using the ‘.then()’ method, you can execute functions only after the Promise has been resolved, ensuring that any dependent operations do not proceed until the necessary data is available. Here’s a simple implementation example.

function delayedAddition(a, b, delay) {
  return new Promise((resolve) => {
    setTimeout(() => {
      resolve(a + b);
    }, delay);
  });
}

delayedAddition(5, 7, 2000).then((sum) => {
  console.log('The sum is:', sum);
});

In this example, a function returns a Promise that resolves with the sum of two numbers after a specified delay. Once resolved, the result is available in the ‘.then’ block.

2

Oh, cool question! When you need to handle async operations in JavaScript, promises are like your best friend. They help manage operations that might not complete instantly, like fetching data or doing math after a delay. What’s magic is that with the .then() method, you can wait for the result before moving on.

Here’s a funky way to add two numbers:

function addWithDelay(x, y, waitTime) {
  return new Promise((resolve) => {
    setTimeout(() => {
      resolve(x + y);
    }, waitTime);
  });
}

addWithDelay(6, 8, 2000).then((result) => {
  console.log('Addition result:', result);
});

Just like that - your sum appears after a short wait! If this was helpful, give it a thumbs up if you want!

3

Here’s a simple yet effective solution for managing asynchronous operations using Promises in JavaScript. Promises allow you to handle tasks that might take some time, like performing calculations after a delay, without blocking your code execution. Let’s dive into a practical example that simulates a delayed addition:

function sumAfterDelay(num1, num2, delayTime) {
  return new Promise((resolve) => {
    setTimeout(() => {
      resolve(num1 + num2);
    }, delayTime);
  });
}

sumAfterDelay(3, 9, 2000).then((total) => {
  console.log('Total sum is:', total);
});

How it Works:

  • Creating a Promise: The sumAfterDelay function returns a Promise that will resolve with the sum of num1 and num2 after a delayTime.
  • Using setTimeout: This ensures that the addition is executed after the specified time delay.
  • Resolving and Accessing the Result: Once the Promise resolves, the .then() block lets us access the result to proceed with any further operations.

This approach ensures that dependent operations only execute after the required data is ready, promoting efficient code flow and resource management.