JavaScript ES7 Features: The In-Depth Guide

JavaScript is possibly one of the most popular programming languages currently in use. Over time, it has undergone many changes, and with every new edition of the standard that defines JavaScript, developers get even more powerful features making coding even more efficient and effective. Though ES7, also commonly referred to as ECMAScript 2016, introduced fewer features compared to its earlier predecessors, what it did bring would shape the language to be in a better place. We will be looking into the two main features of JavaScript ES7: Exponentiation Operator and Array.prototype.includes(), and see how they make it easier for development to happen.

1. Exponentiation Operator (**)

Before ES7, one could not compute the power of a number without using the Math.pow() function. The function looked like this:

let result = Math.pow(3, 4); // Result: 81

This method was practical but sometimes clumsy, especially in operations involving more complicated mathematics. The ** exponentiation operator in ES7 is much shorter and easier to read for the same calculation:

let result = 3 ** 4; // Result: 81

Why is this helpful?

• Simplification: It reduces syntax and helps make code easier to read, mostly when handling several calculations.
• Similarity: Users of other languages, like Python, are accustomed to the ** operator, hence their easier introduction to JavaScript.

2. Array.prototype.includes()

One operation developers do most often in JavaScript is checking if an array contains a specific value. Before ES7, developers had to use the indexOf() method:

let fruits = ['apple', 'banana', 'mango']; console.log(fruits.indexOf('banana') !== -1); // Output: true

Although this works, it's not very intuitive, and checking for the existence of a value can get messy. With ES7 comes a much cleaner solution through the introduction of the new method, Array.prototype.includes():

let fruits = ['apple', 'banana', 'mango']; console.log(fruits.includes('banana')); // Output: true

Why is this useful?

• Readability: includes() is more readable and communicates intent nicely. When you read the code, you know you are checking if the array contains a certain value.
• Handles Special Cases: includes() handles NaN correctly, but indexOf() cannot identify whether it's NaN.

let numbers = [1, 2, NaN]; console.log(numbers.includes(NaN)); // Output: true

3. Asynchronous Functions

Though async/await was officially introduced in ES8, its groundwork was laid in ES7 through native support for promises and asynchronous iteration. ES7 enabled developers to work with promises more easily, laying the path for async and await keywords, which would come later.

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

Benefits of ES7 Features

ES7 features, though fewer in number, offer several advantages:

• Improved Developer Experience: By simplifying common tasks like array element checks and exponentiation, ES7 makes JavaScript coding more efficient.
• Cleaner Code: The includes() method and the ** operator keep code concise and maintainable, reducing verbosity.
• Alignment with Other Languages: Features like the exponentiation operator bring JavaScript closer to other languages, aiding developers who work across platforms.
• Foundation for Future Enhancements: ES7 laid the groundwork for future JavaScript improvements, especially in the realm of asynchronous programming.

Conclusion

JavaScript ES7 may have introduced only two major features—Exponentiation Operator and Array.prototype.includes—but both have had a lasting impact on the way developers write code today. These simple yet powerful additions enhance the usability and readability of JavaScript, making development faster and more intuitive. While not as feature-packed as some other ECMAScript versions, ES7 has certainly contributed to JavaScript's evolution into a modern, developer-friendly language.

Published By: Ibrahim
Updated at: 2024-10-15 14:42:47