What is ES8

What is ES8?

ECMAScript 2017, commonly referred to as ES8, is the eighth edition of the ECMAScript language specification. It was officially released in June 2017 and brought several new features and improvements to JavaScript, which is the language that powers both React.js and React Native. ES8 introduced a variety of new functionalities that enhance the efficiency and readability of JavaScript code, making it easier for developers to write and maintain complex applications.

Async/Await

One of the most significant features introduced in ES8 is the async/await syntax. This feature allows developers to write asynchronous code that looks and behaves more like synchronous code, making it easier to read and debug. Async functions return a Promise, and the await keyword can be used inside these functions to pause execution until the Promise is resolved. This is particularly useful in React.js and React Native applications where asynchronous operations, such as API calls, are common.

Object.entries() and Object.values()

ES8 also introduced two new methods for working with objects: Object.entries() and Object.values(). Object.entries() returns an array of a given object’s own enumerable string-keyed property [key, value] pairs, while Object.values() returns an array of the object’s own enumerable property values. These methods simplify the process of iterating over objects and extracting data, which can be particularly useful in state management and component rendering in React.js and React Native.

String Padding

String padding is another feature added in ES8, with the introduction of the padStart() and padEnd() methods. These methods allow developers to pad the current string with another string until the resulting string reaches the desired length. This can be useful for formatting output in user interfaces, ensuring that strings align correctly in tables or other structured layouts in React.js and React Native applications.

Trailing Commas in Function Parameter Lists and Calls

ES8 allows trailing commas in function parameter lists and calls, which can make version control diffs cleaner and editing code easier. This feature is particularly beneficial in collaborative environments where multiple developers are working on the same codebase, as it reduces the likelihood of syntax errors and improves code readability.

Shared Memory and Atomics

Shared memory and atomics are advanced features introduced in ES8 that enable low-level synchronization between threads. These features are crucial for performance optimization in complex applications, allowing developers to manage shared data more efficiently. While not commonly used in everyday React.js and React Native development, they can be essential for specific performance-critical tasks.

Object.getOwnPropertyDescriptors()

The Object.getOwnPropertyDescriptors() method was introduced in ES8 to return all own property descriptors of a given object. This method is useful for creating shallow copies of objects, merging objects, and implementing certain design patterns. In React.js and React Native, this can be particularly helpful for managing component state and props, ensuring that objects are handled correctly and efficiently.

Function.prototype.toString()

ES8 standardized the behavior of the Function.prototype.toString() method, ensuring that it returns an exact representation of the source code of the function. This can be useful for debugging and logging purposes, allowing developers to inspect the exact implementation of functions. In the context of React.js and React Native, this can aid in understanding component behavior and tracking down issues.

Improved Unicode Support

ES8 improved Unicode support in JavaScript, including better handling of Unicode property escapes in regular expressions. This enhancement is particularly useful for internationalization and localization of React.js and React Native applications, ensuring that text processing and validation work correctly with a wide range of characters and scripts.

Promise.prototype.finally()

The Promise.prototype.finally() method was introduced in ES8 to allow developers to specify a callback that will be executed when a Promise is settled, regardless of whether it was resolved or rejected. This is useful for cleaning up resources or performing other finalization tasks in asynchronous operations. In React.js and React Native, this can help manage side effects and ensure that application state remains consistent after asynchronous operations complete.