JavaScript

async vs sync function

Synchronous Functions:

Execute code line by line, in sequence
Each operation must complete before moving to the next one
Block the execution of other code while running

1function makeSandwich() {
2  let bread = getBread(); // Must complete before moving on
3  let cheese = getCheese(); // Waits for bread first
4  let sandwich = bread + cheese;
5  return sandwich;
6}

Asynchronous Functions:

Allow other code to run while waiting for operations to complete
Don't block execution
Often used for operations that might take time (API calls, file operations, etc.)
Use keywords like async and await, or work with Promises

1async function orderFood() {
2  console.log('Ordering food...');
3
4  try {
5    // await lets us wait for the promise to resolve
6    const food = await fetch(
7      'https://api.restaurant.com/order'
8    );
9    console.log('Food has arrived!');
10    return food;
11  } catch (error) {
12    console.log('Error ordering food:', error);
13  }
14}
15
16// This code runs while food is being ordered
17console.log('Doing other things while waiting for food...');

What is difference between sync and async function?

async vs sync function

Synchronous Functions:

Asynchronous Functions:

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