Summary 简介 ECMAScript 2022 (ES13) Class Fields RegExp Match Indicess Top-level await ECMAScript 2021 (ES12) String.prototype.replaceAll Promise.any WeakRefs Logical Assignment Operators Numeric Separators ECMAScript 2020 (ES11) String.prototype.matchAll Dynamic Import BigInt Promise.allSettled globalThis for-in mechanics Optional Chaining Nullish coalescing Operator import.meta ECMAScript 2019 (ES10) Optional catch binding JSON superset Symbol.prototype.description Function.prototype.toString Object.fromEntries Well-formed JSON.stringify String.prototype.{trimStart,trimEnd} Array.prototype.{flat,flatMap} ECMAScript 2018 (ES9) Template Literal Revision s/dotAll flag for regular expressions RegExp Named Capture Groups Object Rest/Spread Properties RegExp Lookbehind Assertions Unicode property escapes in regular expressions Promise.prototype.finally Async Iteration ECMAScript 2017 (ES8) Async / Await Shared Memory and Atomics Object.values / Object.entries String padding Trailing comma Object.getOwnPropertyDescriptors ECMAScript 2016 (ES7) Array.prototype.includes 求幂运算符(**)