Es11

ES11, short for ECMAScript 2020, is the eleventh edition of the ECMAScript language specification. Published in 2020 by TC39, it defines a set of new features and semantics for JavaScript across engines and environments. As with previous editions, ES11 aims to improve language ergonomics, safety, and developer productivity without altering core behavior of existing code in unexpected ways. The edition builds on the preceding ES10 and is widely implemented in modern runtimes and browsers.

Major additions include BigInt, a new primitive type for arbitrary-length integers; optional chaining and the nullish coalescing operator; Promise.allSettled and Promise.any; globalThis; and String.prototype.matchAll. BigInt allows precise arithmetic beyond the limits of Number, represented with the suffix n (for example, 123n) and the BigInt constructor. Optional chaining (a?.b) and nullish coalescing (a ?? b) provide safer property access and more predictable defaulting when values are null or undefined. Promise.allSettled waits for all promises and reports their outcomes, while Promise.any resolves as soon as any promise fulfills. The globalThis object offers a universal global scope across environments, and String.prototype.matchAll returns an iterator over all matches of a pattern, including capturing groups.

Other changes include enhancements to module semantics and metadata, such as import.meta, and incremental improvements to standard library features. Adoption varies by platform, with all major browsers and Node.js providing substantial support in recent releases. When targeting older environments, developers may rely on transpilers and polyfills to maintain compatibility.