ES2019 Features: What Even Are They?
summary
Lists concrete stage‑4 changes, compatibility notes and the real tradeoffs: trimStart/trimEnd and Symbol.prototype.description land and Node versions matter; optional catch binding removes the catch parameter (sparking debates about silently swallowing errors); Array.prototype.sort switches to a stable Timsort implementation; flatMap semantics (map then flatten) and the naming dustup with a polyfill cause compatibility fuss; Object.fromEntries appears and test262 compliance plus polyfills determine when features actually work in practice.
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chapters (11)
- 0:00Intro
- 2:52Pitfalls
- 6:57Trim
- 8:15Prototype Description
- 9:20Compatibility Charts
- 9:54Optional Catch Binding
- 11:19Error Handling
- 15:10FlatMap
- 17:10Smoosh
- 18:37Object from Entries
- 20:29Wrapup
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