proposal-do-expressions VS proposal-iterator-helpers

> no pattern matching/switch expressions

They're still waiting on the do expression proposal for that (https://github.com/tc39/proposal-do-expressions), which has been in the bikeshedding stage for the past five years.

At some point, it may be superseded by do blocks, but for now it's really your best bet.

But there is a proposal for do-expression : https://github.com/tc39/proposal-do-expressions

It's also the reason why do expressions are my most anticipated feature for JS.

> They should repurpose `do` so that `do {}` (without the `while`) is an expression that you can put statements inside and return the last statement.

There's a proposal for precisely that. Unfortunately, only Stage 1 though.

https://github.com/tc39/proposal-do-expressions

It's one of the main reasons why I really want the do-expression propsal to work out, because then it would become:

Do blocks. Okay, this is actually a proposal so maybe someday. Basically blocks that can resolve to an expression.

Tomorrow, do expressions:

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...

Once this https://github.com/tc39/proposal-iterator-helpers reaches browsers, I'm prob gonna be exclusively using Maps.

No, probably not. But with iterator helpers, you can do

> 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

Upcoming: https://github.com/tc39/proposal-iterator-helpers

Not Generators, but Iterators have a Stage 3 proposal with helpers like these.

I guess you are not the only one dealing with this. That’s why there is this proposal https://github.com/tc39/proposal-iterator-helpers So hopefully it will get easier soon. But in most cases you can simply wrap it in Array.from or you can also clone with the spread operator.

Let's assume Number.range(), iterator helpers and some isPrime() function. From that we could easily create the following: