Things You Don't Know About JavaScript in 2023
summary
TC39 uses a five‑stage proposal pipeline and features only become official after two independent engine implementations and full test coverage, so many additions are already shipping in engines long before they reach Stage 4. Practical arrivals include matchAll for grouped regex matches, negative indexing via .at, non‑mutating array methods (toReversed/toSpliced) available on Node 20, and Promise.any/Promise.allSettled semantics. Upcoming items: Records and Tuples at Stage 2, Temporal polyfill widely used, iterator helpers and ShadowRealm moving through the stages.
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chapters (7)
- 0:00Introduction to TC39
- 2:06The TC39 standards process
- 6:44Recent JavaScript features
- 15:14Upcoming language features
- 23:36Regex, promises, and realms
- 30:15Temporal and future proposals
- 37:00Q&A session
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