What’s new in JavaScript
summary
Chrome/V8 claims concrete wins: raw JS parsing is doubled since Chrome 61, with 40% of parsing moved off the main thread; promises run up to 11× faster (Promise.all up to 13× from Node 7→12) and memory is down ~20% on Android Go (Chrome 70→76). Language work is landing: private # fields, String.prototype.matchAll, numeric separators, BigInt with toLocaleString/Intl.NumberFormat, Array.flat/flatMap, Object.fromEntries, globalThis, stable Array.sort, new Intl APIs, Promise.allSettled ships (Chrome 76), Promise.any and WeakRefs remain experimental.
AI-written summary · about
chapters (15)
- 0:00Introduction to V8
- 2:32Real-world performance
- 4:20JavaScript feature updates
- 5:30Class fields and syntax
- 8:25String match all API
- 9:53Numeric separators
- 11:05BigInt and formatting
- 13:14Array flat and flatMap
- 14:43Object from entries
- 17:31Global this and stability
- 19:53Stable array sorting
- 21:58Localization APIs
- 27:21Async and promises
- 28:54Promise combinators
- 32:28Weak refs and conclusion
