es6

ECMAScript (often abbreviated as ES) is the standard specification that JavaScript (JS) is based on. Therefore, you can say that JavaScript is an implementation of ECMAScript.

Explanation:

• ECMAScript: It is a scripting language specification standardized by ECMA International. The specification outlines the core features, syntax, and semantics of the language.
• JavaScript: It is a programming language that implements the ECMAScript standard along with additional features and APIs (such as the Document Object Model, or DOM) that are specific to web development.

In summary, JavaScript is part of ECMAScript, as it adheres to the ECMAScript standards while also extending them with additional capabilities.

ES6 essentials

In this section we are going to cover essential js features that we are going to use in react applications, such as:

Let/Const Objects this Arrow functions Object Destructuring Spread Classes Modules

ES6 Cheat Sheet

1. Let and Const Let: Block-scoped variable declaration. Const: Block-scoped, read-only constant declaration.

let name = "John"; const age = 30;

2. Arrow Functions Shorter syntax for function expressions. Lexically binds this.

const add = (a, b) => a + b;

3. Template Literals Multi-line strings and string interpolation.

const greeting = Hello, ${name};

4. Destructuring Assignment Unpack values from arrays or properties from objects into distinct variables.

const person = { name: "John", age: 30 }; const { name, age } = person;

const numbers = [1, 2, 3]; const [one, two, three] = numbers;

5. Default Parameters Default values for function parameters.

function multiply(a, b = 1) { return a * b; }

6. Spread Operator Expands an iterable (like an array) into more elements.

const nums = [1, 2, 3]; const moreNums = [...nums, 4, 5];

7. Rest Parameters Represents an indefinite number of arguments as an array.

function sum(...numbers) { return numbers.reduce((acc, curr) => acc + curr, 0); }

8. Modules Import and export functionalities between files.

// Exporting export const pi = 3.14;

// Importing import { pi } from './math.js';

9. Classes Syntactical sugar over JavaScript's existing prototype-based inheritance.

class Person { constructor(name) { this.name = name; } greet() { console.log(Hello, my name is ${this.name}); } }

10. Promises Represents the eventual completion (or failure) of an asynchronous operation.

const fetchData = () => { return new Promise((resolve, reject) => { // Asynchronous code }); };

11. Iterators and Generators Iterators: Objects that allow iteration over a collection. Generators: Functions that can be exited and later re-entered.

function* generator() { yield 1; yield 2; }

const gen = generator(); console.log(gen.next()); // { value: 1, done: false }

12. Map and Set Map: Collection of key-value pairs. Set: Collection of unique values.

const map = new Map(); map.set('key', 'value');

const set = new Set([1, 2, 2, 3]);

Conclusion This cheat sheet covers the essentials of ES6, providing a quick reference for developers.

This cheat sheet has been created by Blessing Baloyi with the help of: https://youtu.be/NCwa_xi0Uuc?si=knAHyTscYUg1pSaU and ZebraGPT