Record/Tuple objects are immutable primitives with structural equality, not object reference equality. So little relation to AS3 Dictionary/ES6 Map, besides being possible keys for Map/Set.
TIL and also god that would be amazing, almost to the point of making JS/TS actually nice if done right (what’s next, pattern matching?). The number one footgun in JS imo is the combination of mutability and reference copying. Immutable or at least easy-to-copy plain old data is fantastic when it is well supported in the language.
Oh boy do I have news for you... https://tc39.es/proposal-pattern-matching/
:P