On: Node v8.0.0 Released

[ujal]

There should also be something like

  awaitAll 

to replace

  await Promise.all 

calls.

[adrusi → ujal]

There are many ways to compose promises, no point in elevating some of them to keyword status. If you need to do anything interesting with promises, just use a promises library. The point of async/await is to free you from having to use callbacks, not to eliminate the need for libraries.

[ujal → adrusi]

Every async function will return a Promise anyway. I am simply interested in resolving a collection of Promises in a clean way.

[always_good → ujal]

I don't see what's unclean about Promise.all or how creating a 1:1 alias for it makes it cleaner.

Also, many times you want to limit the concurrency of your promise execution which isn't something you can do with an array of promises. You'd be back to using `await` + something like https://www.npmjs.com/package/promise.map.

I'm someone that used to use `co` where you could go:

    const [a, b] = yield [promiseA(), promiseB()]

But I prefer the simplicity and consistency of having to use something like Promise.all or require('promise.map').

[ujal → always_good]

Its the ambiguity for new programmers. With something like awaitAll new programmers wouldn't need to learn about Promises at all.

You have a point with concurrency, but handling concurrency is an another beast altogether.

[always_good → ujal]

I have a hard time understanding how adding alias indirection disambiguates anything much less spares one from learning something.

How does one get to the point where they want to await multiple promises, yet they need to be insulated from the very presence of the `Promise` object?

[ujal → always_good]

Well at least in my mental model a Promise is an object that eventually resolves to something within its .then() method. In contrast my mental model of await is that of a blocking call. One can internalize the latter without the former.

[abritinthebay → ujal]

Given Promise.all resolves to an ordered array surely this would work:

    const [foo, bar, baz] = await returnerOfPromiseCollection();

That would assume there was either a) a catch in that collect or b) some error checking, but still...

[bfred_it → abritinthebay]

It "works" but foo won't contain the resolved value, just the promise.

The code is awaiting an array, which is already "resolved" and its returned right away. Its contents are not relevant to `await`.

[abritinthebay → bfred_it]

You are correct! My apologies = I misremembered how that works >_<

Yes, once you have a promise you have to deal with it as such through the whole chain.

[bfred_it → ujal]

Promise.all is not even that good. If one fails, the rest of the Promises are lost. It does not wait for all Promises.

I prefer something like p-settle most of the time https://github.com/sindresorhus/p-settle

[Ajedi32 → ujal]

Pretty sure there used to be a syntax in the spec for handling that. Something like `await*` I believe. It got removed pretty early on in the process though.

[ujal → Ajedi32]

Any interesting reasons as to why?

[Ajedi32 → ujal]

I wasn't really involved in those discussions, but I suspect it's for similar reasons to what others in the comments here are arguing; they wanted to keep the syntax minimal and decided that adding a special syntactic sugar for something that could already be accomplished by `Promise.all(...)` was unnecessary.

[steve_adams_86 → ujal]

You can make it yourself fairly easily I guess:

    const awaitAll = Promise.all.bind(Promise);

    async function foo() {
        var [val1, val2] = await awaitAll([func1, func1]);
    }

It isn't ideal but it's a little cleaner

[nailer → steve_adams_86]

+1. I'm a big fan of top level function binds to remove boilerplate and keep code readable:

  const log = console.log.bind(console), 
    query = document.querySelector.bind(document),
    queryAll = document.querySelectorAll.bind(document);

[RReverser → nailer]

You don't need to bind `console.log` by the way (at least not in any recent version of Node.js or browsers).

[ujal → steve_adams_86]

  await all([fn1, fn2]) ;)

i wonder when we will get s-expressions for function calls

  (awaitAll [fn1, fn2])

[doublerebel → ujal]

Just write (iced) coffeescript, s-exp are totally valid there:

https://github.com/nextorigin/riemann-query-parser/blob/mast...

[ujal → doublerebel]

Yeah, s-exps are the only thing I miss :(

[krisdol → ujal]

You can use .map to call await on every element in the array, or define a new function so you don't have to write that all the time:

    const awaitAll = (futures) => futures.map(f => await f);

edit: this is wrong but I can't delete it. Haven't used async as much as promises.

[ujal → krisdol]

Well an async function always returns a Promise. await simply blocks until the Promise is resolved to continue execution. Thats why I am wondering why they decided to await only on a single Promise.

[ujal → krisdol]

Don't you need to be in an async context to call await?