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Async/Await is finally back in Zig

(charlesfonseca.substack.com)
39 points barddoo | 2 comments | | HN request time: 0.001s | source
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ajross ◴[] No.45782414[source]
Is it time now to say that async was a mistake, a-la C++ exceptions? The recent futurelock discussion[1] more or less solidified for me that this is all just a mess. Not just that one bug, but the coloring issue mentioned in the blog post (basically async "infects" project code requiring that you end up porting or duplicating almost everything -- this is especially true in Python). The general cognitive load of debugging inside out code is likewise really high, even if the top-level expression of the loop generator or whatever is clean.

And it's all for, what? A little memory for thread stacks (most of which ends up being a wash because of all the async contexts being tossed around anyway -- those are still stacks and still big!)? Some top-end performance for people chasing C10k numbers in a world that has scaled into datacenters for a decade anyway?

Not worth it. IMHO it's time to put this to bed.

[1] No one in that thread or post has a good summary, but it's "Rust futures consume wakeup events from fair locks that only emit one event, so can deadlock if they aren't currently being selected and will end up waiting for some other event before doing so."

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jayd16 ◴[] No.45782502[source]
I really wish people would get over the coloring meme.

Knowing if a function will yield the thread is actually extremely relevant knowledge you want available.

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Calavar ◴[] No.45782601[source]
Of course it's useful, that's why function modifiers like 'const' or 'virtual' (thinking from a C++ perspective) are widely seen as useful, but making one function virtual doesn't force you to propagate that all the way up the call tree.
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1. jayd16 ◴[] No.45782733[source]
Const is similar, now that you mention it.
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2. Calavar ◴[] No.45782784[source]
Const is the reverse.

Constness is infectious down the stack (the callee of a const function must be const) while asyncness is infectious up the stack (the caller of an async function must be async). So you can gradually add constness to subsections of a codebase while refactoring, only touching those local parts of the codebase. As opposed to async, where adding a single call to an async function requires you to touch all functions back up to main