Tone down explanation on RefCell::get_mut #101389
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This is great. Thank you! @bors r+ rollup |
Dylan-DPC
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Tone down explanation on RefCell::get_mut
The language around `RefCell::get_mut` is remarkably sketchy and especially to the novice seems to quite strongly discourage using the method ("be cautious", "Also, please be aware", "special circumstances", "usually not what you want"). It was added six years ago in rust-lang#40634 due to confusion about when to use `get_mut` and `borrow_mut`.
While its signature limits the use-cases for `get_mut`, there is no chance for a safety footgun, and readers can be made aware of `borrow_mut` more softly. I've also just sent a [PR](rust-lang/rust-clippy#9044) to lint situations where `get_mut` could be used to improve ergonomics and performance.
So this PR tones down the language around `get_mut` and also brings it more in line with [`std::sync::Mutex::get_mut()`](https://doc.rust-lang.org/stable/std/sync/struct.Mutex.html#method.get_mut).
bors
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…iaskrgr Rollup of 11 pull requests Successful merges: - rust-lang#101389 (Tone down explanation on RefCell::get_mut) - rust-lang#101798 (Make `from_waker`, `waker` and `from_raw` unstably `const`) - rust-lang#101881 (Remove an unused struct field `late_bound`) - rust-lang#101904 (Add help for invalid inline argument) - rust-lang#101966 (Add unit test for identifier Unicode emoji diagnostics) - rust-lang#101979 (Update release notes for 1.64) - rust-lang#101985 (interpret: expose generate_stacktrace without full InterpCx) - rust-lang#102004 (Try to clarify what's new in 1.64.0 ffi types) - rust-lang#102005 (rustdoc: remove unused CSS `td.summary-column`) - rust-lang#102017 (Add all submodules to the list of directories tidy skips) - rust-lang#102019 (Remove backed off PRs from relnotes) Failed merges: r? `@ghost` `@rustbot` modify labels: rollup
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The language around
RefCell::get_mutis remarkably sketchy and especially to the novice seems to quite strongly discourage using the method ("be cautious", "Also, please be aware", "special circumstances", "usually not what you want"). It was added six years ago in #40634 due to confusion about when to useget_mutandborrow_mut.While its signature limits the use-cases for
get_mut, there is no chance for a safety footgun, and readers can be made aware ofborrow_mutmore softly. I've also just sent a PR to lint situations whereget_mutcould be used to improve ergonomics and performance.So this PR tones down the language around
get_mutand also brings it more in line withstd::sync::Mutex::get_mut().