proposal-record-tuple VS proposal-array-grouping

relevant issue, which is at the crux of this problem: https://github.com/tc39/proposal-record-tuple/issues/387

There are still so many basic things that aren't in the JS stdlib, though. A good example is Map - if you need to use a tuple of two values as a key, you're SOL because there's no way to customize key comparisons. Hopefully we'll get https://tc39.es/proposal-record-tuple/ eventually, but meanwhile languages ranging from C++ to Java to Python have had some sensible way to do this for over 20 years now.

If you’re reaching for structuredClone, what you really want is native immutable Record and Tuple syntax, and the companion “deep path properties” syntax which allows for efficient and ergonomic immutable updates:

- https://github.com/tc39/proposal-record-tuple

It will be called "record" in JavaScript which will swing the popularity back the other way I guess (currently a language proposal)

I suspect considering the strong desire to maintain consistency with JavaScript, we will eventually see something that when the Record proposal passes through tc39

I hope the Record and Tuple proposal makes it through

I mean, I'd love some real immutable/persistent data structures in JS by default, or even some Immer-like syntax sugar. Something like the record/tuple proposal would be awesome.

This will become very useful once Records and Tuples are a thing, because it allows you to store object references in a record/tuple (which by definition can only contain primitives).

Record and tuple is at stage 2

Also, js has an ongoing immutable value data types proposal.

Global iterator type is coming: https://github.com/tc39/proposal-iterator-helpers

But a method named `groupBy` on iterators traditionally means a different thing: https://github.com/tc39/proposal-array-grouping/issues/51#is...

Global iterable type it's too late for, since there's many extant iterables in the language and on the web which don't have it in their prototype chain and can't reasonably be changed.

Array grouping to combine like data into groups using Object.groupBy() and Map.groupBy().

Array Grouping: A proposal to make grouping of array items easier.

They are coming out with array.group() soon, which is supposed to also fulfil the use-case of partitioning :) - https://github.com/tc39/proposal-array-grouping.

https://github.com/tc39/proposal-array-grouping for those curious

I'm also looking forward to map.emplace() and arr.group() and iterator helpers.

At the end of the day, it comes down to whether browser vendors are willing to ship the feature even though it breaks said websites, and they do have visitor data to back those decisions. If the rule was "never break any website ever", you'd be able to block proposals you don't personally like by crafting a website that "gets broken" by that proposal.

At least in the array grouping proposal, they did evaluate amount and popularity of possibly breaking sites, before eventually renaming the method from .groupBy to .group

https://github.com/tc39/proposal-array-grouping/issues/37

The proposal is described here.

Remarkably, this is now a TC39 proposal.

Proposal, Polyfill