7 New JavaScript Features (And 2 I'm Still Waiting For)

Short summary

ECMAScript 2026 adds three useful features for JavaScript developers. Map.getOrInsert() and getOrInsertComputed() eliminate boilerplate for default values and caching patterns. Iterator.concat() merges multiple iterators without materializing data in memory, while Array.fromAsync() converts async iterators and promise arrays into arrays. Code examples demonstrate practical improvements.

• •Map.getOrInsert() and getOrInsertComputed() simplify default-value patterns and caching
• •Iterator.concat() elegantly merges multiple iterators without materializing all data in memory
• •Array.fromAsync() converts async iterators and promise arrays into consolidated arrays

Generated with AI, which can make mistakes.