proposal-iterator-helpers

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.

Very much agreed. The amount of mileage we get from using Spread (literally the ...) alone has been amazing. https://developer.mozilla.org/en-US/docs/Web/JavaScript/Refe... Iteration helpers is shipping soon, that'll be a huge help (async iteration helpers will be delayed for a while). https://github.com/tc39/proposal-iterator-helpers . In the olden days, I feel like the codebases I worked on needed to use .apply() multiple times a week, to figure out some creative way of invoking functions. https://developer.mozilla.org/en-US/docs/Web/JavaScript/Refe... That's all gone now; I'd take even odds that 50% of my team knows .call and .apply. Chrome 117 is shipping Object.groupBy() and that's gonna be a huge help in eliminating a lot of the last places we end up using lodash. https://developer.mozilla.org/en-US/docs/Web/JavaScript/Refe...

There are now builtin iterator versions of most of these looped functions [1], should be shipping in stable Chrome next month. The "give me an array at the end" function is spelled toArray. But it's not going to help all that much with this problem. The iterator protocol in JS involves an allocation for every individual value, and while in some cases that can be optimized out, it's pretty tricky to completely optimize. It's always going to be difficult to beat a c-style for loop for performance. [1] https://github.com/tc39/proposal-iterator-helpers/

> focus more on improving the terrible JS web API That's W3C’s job, not ECMA’s. > Where are all the containers? ? > Sorted sets/maps? Sets and Maps are sorted (by insertion order) > Why can't I even map an iterator? It's coming, but someone will likely be exhausted by that addition. https://github.com/tc39/proposal-iterator-helpers

As much as I like these concepts, I'd be hesitant about adding them to the language. At what point does a language support too many paradigms? In contrast, take the recently stage-3'd Iterator Helpers[0]. These build on top of the language by using methods that already exists in other parts. It feels natural and is more of the same. 0 - https://github.com/tc39/proposal-iterator-helpers#implementa...