[diondokter]

Various prominent people have said years after that .await was the correct choice after all

[steveklabnik]

I was initially very against postfix await and I was wrong. It's great.

[staticassertion]

I'm not prominent but I disagreed with it at the time and I was wrong.

[adastra22]

I’m curious - why were you wrong? It still seems like a wart to me, all these years later. What am I missing?

[tracker1]

Contrast it with async in JS/ES as an example... now combine it with the using statement for disposeAsync instances.

    await using db = await sqlite.connect(await ctx.getConfig("DB_CONN"));

It's not so bad when you have one `await foo` vs `foo.await`, it's when you have several of them on a line in different scopes/contexts.

Another one I've seen a lot is...

    const v = await (await fetch(...)).json();
    

Though that could also be...

    const v = await fetch(...).then(r => r.json());

In any case, it still gets ugly very quickly.

[adastra22]

I’ve never in my life used JS, so I’ll have to take your word for it.

[tracker1]

It's a language I'm familiar with that uses the `await foo` syntax and often will see more than one in a line, per the examples given. C# is the most prominent language that has similar semantics that I know well, but is usually less of an issue there.

[fluffybucktsnek]

I'll give my two cents here. I work with Dart daily, and it also uses the `await future` syntax. I can cite a number of ergonomic issues:

```dart (await taskA()).doSomething() (await taskB()) + 1 (await taskC()) as int ```

vs.

```rust taskA().await.doSomething() taskB().await + 1 taskC().await as i32 ```

It gets worse if you try to compose:

```dart (await taskA( (await taskB( (await taskC()) as int )) + 1) ).doSomething() ```

This often leads to trading the await syntax for `then`:

```dart await taskC() .then((r) => r as i32) .then(taskB) .then((r) => r + 1) .then(taskA) .then((r) => r.doSomething()) ```

But this is effectively trading the await structured syntax for a callback one. In Rust, we can write it as this:

```rust taskA(taskB(taskC().await as i32).await + 1).await.doSomething() ```

[Jtsummers]

Two spaces before a line make it a code block literal

  This is a code block

HN has never used markdown so the triple-tick does nothing but create noise here.

[fluffybucktsnek]

Thnaks for heads up, I'll keep this in mind in the future.

[staticassertion]

I was a proponent of the postfix macro solution. `.await!` or `.await!()`, essentially. The idea was that this could be generalized, it was closer to existing syntax, etc.

I was worried about features that I still don't love like `.match` etc (I'm more open to these now).

Post-fix macros would have been very complex. Scoping alone is complex.

`.await` kinda just works. It does everything you want and the one cost is that it looks like a property access but it isn't. A trivial cost in retrospect that I was a huge baby about, and I'll always feel bad about that.

[adastra22]

The postfix macro does sound like a better solution tbh. Did you write the static assertions crate? If so, thank you. I’m a daily user.

[staticassertion]

Ha, no, I did not write that crate. I think my use of this username probably predates rust, certainly that crate.

Postfix macros had some very tricky issues and it would have delayed things a lot to figure out the right resolution.