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57 lines
1.0 KiB
Rust
57 lines
1.0 KiB
Rust
//@ check-pass
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#![feature(thread_local)]
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#![deny(tail_expr_drop_order)]
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use std::marker::PhantomData;
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use std::ops::{Deref, DerefMut};
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pub struct Global;
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#[thread_local]
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static REENTRANCY_STATE: State<Global> = State { marker: PhantomData, controller: Global };
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pub struct Token(PhantomData<*mut ()>);
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pub fn with_mut<T>(f: impl FnOnce(&mut Token) -> T) -> T {
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f(&mut REENTRANCY_STATE.borrow_mut())
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}
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pub struct State<T: ?Sized = Global> {
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marker: PhantomData<*mut ()>,
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controller: T,
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}
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impl<T: ?Sized> State<T> {
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pub fn borrow_mut(&self) -> TokenMut<'_, T> {
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todo!()
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}
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}
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pub struct TokenMut<'a, T: ?Sized = Global> {
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state: &'a State<T>,
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token: Token,
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}
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impl<T> Deref for TokenMut<'_, T> {
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type Target = Token;
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fn deref(&self) -> &Self::Target {
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todo!()
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}
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}
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impl<T> DerefMut for TokenMut<'_, T> {
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fn deref_mut(&mut self) -> &mut Self::Target {
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todo!()
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}
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}
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impl<T: ?Sized> Drop for TokenMut<'_, T> {
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fn drop(&mut self) {
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todo!()
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}
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}
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fn main() {}
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