alt Hacker NewsFor the Rust inclined, [[nodiscard]] is #[must_use], if you were confused.
Anyway, this article illustrates a great reason why C++ is a beautiful mess. You can do almost anything with it, and that comes at a cost. It's the polar opposite ethos of "there should be one clear way to do something" and this sort of thing reminds me why I have replaced all of my systems language needs with Rust at this point, despite having a very long love/hate relationship with both C and C++.
Totally agree it should be marked as nodiscard, and the reasoning for not doing so is a good example of why other languages are taking over.
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It’s also worth noting that in rust you don’t need to be as worried about marking a function #[must_use] if there is a valid reason some of the time to discard the value. One can just assign like so `let _ = must_use_fn()` which discards the value and silences the warning. I think this makes the intent more clear than casting to void as TFA discusses.
I disagree with the conclusion, other languages are taking over because they have the advantage of not having 40 years of production code history, and those adopting them don't care about existing code.
You will find similar examples in Python, Java, C#,... and why not everyone is so keen into jumping new language versions.
Interestingly Index::index is also usually not marked as `#[must_use]` in Rust either.
I'm not a fan of nodiscard because it's applied way too freely, even if the return value is not relevant. E.g. WebGPU/WGSL initially made atomics nodiscard simply because they return a value, but half the algorithms that use atomics only do so for the atomic write, without needing the return value. But due to nodiscard you had to make a useless assignment to an unused variable.