What are promises in Javascript

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Async/await is a feature in JavaScript that allows for asynchronous programming using a more synchronous-like syntax. It is built on top of Promises and provides a simpler way to write asynchronous code, making it easier to understand and maintain.

In JavaScript, asynchronous operations are typically handled using callbacks or Promises. However, these approaches can lead to callback hell or complex Promise chains, making the code harder to read and debug. Async/await solves this problem by allowing us to write asynchronous code that looks and behaves like synchronous code.

To use async/await, we need to define an asynchronous function using the async keyword. This function can then use the await keyword to pause the execution until a Promise is resolved or rejected. The await keyword can only be used inside an async function.

Here’s an example of how async/await can be used:

async function fetchData() {
try {
const response = await fetch('https://api.example.com/data');
const data = await response.json();
console.log(data);
} catch (error) {
console.log('Error:', error);
}
}
fetchData();

In the above example, the fetchData function is defined as an async function. Inside the function, we use the await keyword to pause the execution until the fetch request is resolved. Once the response is received, we use await again to parse the response as JSON. If any error occurs during the execution, it will be caught in the catch block.

Async/await greatly simplifies the handling of asynchronous operations, making the code more readable and maintainable. It allows developers to write asynchronous code in a more synchronous style, without sacrificing the benefits of non-blocking operations.

Here’s an example of how the above code can be written in HTML format:

<!DOCTYPE html>
<html>
<head>
<title>Async/Await Example</title>
<script>
async function fetchData() {
try {
const response = await fetch('https://api.example.com/data');
const data = await response.json();
console.log(data);
} catch (error) {
console.log('Error:', error);
}
}
fetchData();
</script>
</head>
<body>
<!-- HTML content -->
</body>
</html>

Note: The above HTML code assumes that the JavaScript code is placed within the <script> tag in the <head> section.