mirror of https://github.com/rust-lang/rust.git
42 lines
1021 B
Rust
42 lines
1021 B
Rust
//@ known-bug: #123917
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//@ compile-flags: -Zmir-opt-level=5 -Zpolymorphize=on
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use std::marker::PhantomData;
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pub struct Id<'id>();
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pub struct Item<'life, T> {
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data: T,
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}
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pub struct Token<'life, 'borrow, 'compact, 'reborrow, T>
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where
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'life: 'reborrow,
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T: Tokenize,
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{
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ptr: *mut <T as Tokenize>::Tokenized,
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ptr: core::ptr::NonNull<T::Tokenized>,
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_phantom: PhantomData<Id<'life>>,
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}
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impl<'life> Arena<'life> {
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pub fn tokenize<'before, 'compact, 'borrow, 'reborrow, T, U>(
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item: Item<'life, &'before mut T>,
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) -> Token<'life, 'borrow, 'compact, 'reborrow, U>
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where
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T: Tokenize<'life, 'borrow, 'compact, 'reborrow, Untokenized = U>,
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T::Untokenized: Tokenize<'life, 'borrow, 'compact, 'reborrow>,
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{
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let dst = item.data as *mut T as *mut T::Tokenized;
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Token {
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ptr: core::ptr::NonNull::new(dst as *mut _).unwrap(),
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_phantom: PhantomData,
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}
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}
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}
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pub trait Tokenize {
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type Tokenized;
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type Untokenized;
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}
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