Exploring ECMAScript 2017 (ES8): Key Features and Improvements

ECMAScript 2017, also known as ES8, introduced several new features and improvements to the JavaScript programming language. This article provides a beginner-friendly summary of its main points.

Key Features of ES8

1. Async Functions

• Description: Async functions allow you to write asynchronous code in a simpler and more readable way.
• Key Concept: Using async and await keywords, you can handle promises without chaining then() methods.

Example:

async function fetchData() {
    let response = await fetch('https://api.example.com/data');
    let data = await response.json();
    console.log(data);
}
fetchData();

2. Object.entries() and Object.values()

• Description: These methods provide an easy way to get an array of a given object's own enumerable property [key, value] pairs or just the values.
• Key Concepts:
  • Object.entries(obj): Returns an array of a given object's key-value pairs.
  • Object.values(obj): Returns an array of a given object's values.

Example:

const obj = { a: 1, b: 2, c: 3 };
console.log(Object.entries(obj)); // [['a', 1], ['b', 2], ['c', 3]]
console.log(Object.values(obj));  // [1, 2, 3]

3. String Padding

• Description: New methods for padding strings on the left or right to ensure they meet a certain length.
• Key Concepts:
  • String.prototype.padStart(length, string): Pads the current string with another string (repeated, if needed) until the resulting string reaches the given length.
  • String.prototype.padEnd(length, string): Similar but pads at the end.

Example:

console.log('5'.padStart(2, '0')); // '05'
console.log('5'.padEnd(2, '0'));   // '50'

4. Shared Buffers and Atomics

• Description: Introduces shared memory and atomic operations for working with binary data in a more efficient way.
• Key Concepts: This is particularly useful for web workers where you need to share data between threads without copying.

Example:

const sharedBuffer = new SharedArrayBuffer(1024);
const int32View = new Int32Array(sharedBuffer);
Atomics.store(int32View, 0, 100);
console.log(Atomics.load(int32View, 0)); // 100

Conclusion

ECMAScript 2017 (ES8) enhances JavaScript by introducing async functions for better asynchronous programming, new methods for object manipulation, string padding functionalities, and shared memory capabilities. These features collectively make JavaScript more powerful and easier to use for developers.