add as_mut to mutably access owned or mutably borrowed UnsafeCell safely
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datdenkikniet
commented
Mar 23, 2025
| /// | ||
| /// This is analogous to [`core::cell::UnsafeCell::get_mut`]. | ||
| #[track_caller] | ||
| pub fn as_mut(&mut self) -> MutRef<'_, T> { |
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I'm not entirely certain we even need tracking: if we can mutably borrow the value, we already have exclusive access to it, right? And because we borrow it mutably, no one can re-borrow it immutably until the borrow is dropped.
I've added the in-between struct so that someone can double-check my thoughts, but would be great to get some external input on it.
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…rowed `UnsafeCell` safely.
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See title.
This is the equivalent to
core::cell::UnsafeCell::get_mut, but with tracking. Instead of forcing unnecessaryunsafeon users, we can simply give them mutable access to an owned value.An example of where this causes unnecessary unsafe to be used can be found here.