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Flattening Rust’s learning curve

(corrode.dev)
451 points birdculture | 1 comments | 13 May 25 22:25 UTC | HN request time: 0s | source
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Havoc ◴[13 May 25 23:42 UTC] No.43979116[source]▶
I thought it was quite manageable at beginner level…though I haven’t dived into async which I gather is a whole different level of pain
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echelon ◴[13 May 25 23:45 UTC] No.43979133[source]▶
Async and the "function color" "problem" fall away if your entire app is in an async runtime.

Almost 90% of the Rust I write these days is async. I avoid non-async / blocking libraries where possible.

I think this whole issue is overblown.

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bigstrat2003 ◴[14 May 25 00:28 UTC] No.43979433[source]▶
"Just write everything async" is not remotely a good solution to the problem. Not everything needs to be async (in fact most things don't), and it's much harder to reason about async code. The issue is very much not overblown.
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Salgat ◴[14 May 25 01:08 UTC] No.43979650[source]▶
Why is async code harder to reason about? I've been using it in C# and the entire point is that it lets you write callbacks in a way that appears nearly identical to synchronous code. If you dive into concurrency (which is a separate thing but can be utilized with async code, such as joining multiple futures at the same time), that parts hard whether you're doing it with async or with explicit threads.
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1. umanwizard ◴[14 May 25 02:28 UTC] No.43980094{3}[source]▶
> Why is async code harder to reason about?

I don't know about C#, but at least in Rust, one reason is that normal (non-async) functions have the property that they will run until they return, they panic, or the program terminates. I.e. once you enter a function it will run to completion unless it runs "forever" or something unusual happens. This is not the case with async functions -- the code calling the async function can just drop the future it corresponds to, causing it to disappear into the ether and never be polled again.