JS: ECMAScript 2020

By Xah Lee. Date: . Last updated: .

globalThis

a variable for the global object

Nullish Coalescing Operator

Optional Chaining Operator

String.prototype.matchAll

easier way to get all matches and all captures.

Order of Properties

big int

A new number primitive for working with arbitrary precision integers.

const x = 10n;
console.log( typeof x === "bigint" ); // true

also new are typed array of big int:

Dynamic import, the import() syntax

new syntax: import *

import * as xyz from "./xyz.js";

new syntax: export *

xtodo

Dedicated export * as ns from 'module' syntax for use within modules.

import.meta

xtodo

import.meta, a host- populated object available in Modules that may contain contextual information about the Module.

export {abc} from "./xyz.js";
export * from "./xyz.js";

Promise.allSettled

xtodo

A new Promise combinator that does not short-circuit.

Order of for-in loop

Increased standardization of for-in enumeration order.

JavaScript. ECMAScript New Features