Rollup merge of #121302 - GrigorenkoPV:refmutl, r=bjorn3

Remove `RefMutL` hack in `proc_macro::bridge`

From what I can tell, #52812 is now fixed, so there is no longer any need to keep this hack around.
This commit is contained in:
Nilstrieb 2024-02-20 15:13:54 +01:00 committed by GitHub
commit 739f83d906
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2 changed files with 3 additions and 26 deletions

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@ -296,12 +296,7 @@ impl BridgeState<'_> {
/// N.B., while `f` is running, the thread-local state /// N.B., while `f` is running, the thread-local state
/// is `BridgeState::InUse`. /// is `BridgeState::InUse`.
fn with<R>(f: impl FnOnce(&mut BridgeState<'_>) -> R) -> R { fn with<R>(f: impl FnOnce(&mut BridgeState<'_>) -> R) -> R {
BRIDGE_STATE.with(|state| { BRIDGE_STATE.with(|state| state.replace(BridgeState::InUse, f))
state.replace(BridgeState::InUse, |mut state| {
// FIXME(#52812) pass `f` directly to `replace` when `RefMutL` is gone
f(&mut *state)
})
})
} }
} }

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@ -2,7 +2,6 @@
use std::cell::Cell; use std::cell::Cell;
use std::mem; use std::mem;
use std::ops::{Deref, DerefMut};
/// Type lambda application, with a lifetime. /// Type lambda application, with a lifetime.
#[allow(unused_lifetimes)] #[allow(unused_lifetimes)]
@ -15,23 +14,6 @@ pub trait LambdaL: for<'a> ApplyL<'a> {}
impl<T: for<'a> ApplyL<'a>> LambdaL for T {} impl<T: for<'a> ApplyL<'a>> LambdaL for T {}
// HACK(eddyb) work around projection limitations with a newtype
// FIXME(#52812) replace with `&'a mut <T as ApplyL<'b>>::Out`
pub struct RefMutL<'a, 'b, T: LambdaL>(&'a mut <T as ApplyL<'b>>::Out);
impl<'a, 'b, T: LambdaL> Deref for RefMutL<'a, 'b, T> {
type Target = <T as ApplyL<'b>>::Out;
fn deref(&self) -> &Self::Target {
self.0
}
}
impl<'a, 'b, T: LambdaL> DerefMut for RefMutL<'a, 'b, T> {
fn deref_mut(&mut self) -> &mut Self::Target {
self.0
}
}
pub struct ScopedCell<T: LambdaL>(Cell<<T as ApplyL<'static>>::Out>); pub struct ScopedCell<T: LambdaL>(Cell<<T as ApplyL<'static>>::Out>);
impl<T: LambdaL> ScopedCell<T> { impl<T: LambdaL> ScopedCell<T> {
@ -46,7 +28,7 @@ impl<T: LambdaL> ScopedCell<T> {
pub fn replace<'a, R>( pub fn replace<'a, R>(
&self, &self,
replacement: <T as ApplyL<'a>>::Out, replacement: <T as ApplyL<'a>>::Out,
f: impl for<'b, 'c> FnOnce(RefMutL<'b, 'c, T>) -> R, f: impl for<'b, 'c> FnOnce(&'b mut <T as ApplyL<'c>>::Out) -> R,
) -> R { ) -> R {
/// Wrapper that ensures that the cell always gets filled /// Wrapper that ensures that the cell always gets filled
/// (with the original state, optionally changed by `f`), /// (with the original state, optionally changed by `f`),
@ -71,7 +53,7 @@ impl<T: LambdaL> ScopedCell<T> {
})), })),
}; };
f(RefMutL(put_back_on_drop.value.as_mut().unwrap())) f(put_back_on_drop.value.as_mut().unwrap())
} }
/// Sets the value in `self` to `value` while running `f`. /// Sets the value in `self` to `value` while running `f`.