Explicitely drop the started var in examples
#73074
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| /// // Leaving a condition variable's mutex held after we're no longer | ||
| /// // watching it will block and possibly deadlock notifier threads, so |
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I think this is misleading. Just holding the mutex would not be sufficient to block a notifier thread. It just stops a notifier thread (or anything else) from acquiring the same mutex, which is the whole point of a mutex. If I understand correctly, the notify_one call does not block, so there is nothing about the behavior that would be specific to a notifier thread.
| /// // watching it will block and possibly deadlock notifier threads, so | ||
| /// // we explicitely drop it. |
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The salient point is to release the mutex as soon as possible, not to release it explicitly, so I also find this part misleading. Implicit release when it goes out of scope is just as good as long as it happens as soon as possible.
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Then should I just make the comment something like It is sometimes necessary to manually drop the mutex to unlock it as soon as possible. If you need the ressource until the end of the scope, this is not necessary. and put it once in a new example on the mutex type itself ?
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Yeah I think Mutex could use some example code that demonstrates a realistic use case requiring explicit drop.
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Per #73074 (comment) I'll close this and we can follow up in a separate PR adding that example to Mutex.
…ample, r=dtolnay Example about explicit mutex dropping Fixes rust-lang#67457. Following the remarks made in rust-lang#73074, I added an example on the main `Mutex` type, with a situation where there is mutable data and a computation result. In my testing it is effectively needed to explicitly drop the lock, else it deadlocks. r? @dtolnay because you were the one to review the previous PR.
…ample, r=dtolnay Example about explicit mutex dropping Fixes rust-lang#67457. Following the remarks made in rust-lang#73074, I added an example on the main `Mutex` type, with a situation where there is mutable data and a computation result. In my testing it is effectively needed to explicitly drop the lock, else it deadlocks. r? @dtolnay because you were the one to review the previous PR.
…ample, r=dtolnay Example about explicit mutex dropping Fixes rust-lang#67457. Following the remarks made in rust-lang#73074, I added an example on the main `Mutex` type, with a situation where there is mutable data and a computation result. In my testing it is effectively needed to explicitly drop the lock, else it deadlocks. r? @dtolnay because you were the one to review the previous PR.
Fixes #67457.
I added the explicit drop with an explanation, it is enough ?