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What is difference between sync and async function?

What is difference between sync and async function?

What is difference between sync and async function?

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
javascript
function makeSandwich() {
let bread = getBread(); // Must complete before moving on
let cheese = getCheese(); // Waits for bread first
let sandwich = bread + cheese;
return sandwich;
}

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
javascript
async function orderFood() {
console.log('Ordering food...');
try {
// await lets us wait for the promise to resolve
const food = await fetch(
'https://api.restaurant.com/order'
);
console.log('Food has arrived!');
return food;
} catch (error) {
console.log('Error ordering food:', error);
}
}
// This code runs while food is being ordered
console.log('Doing other things while waiting for food...');

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