Possible approach to fix #71 #72
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Only a draft since this does not explain the lifetime parameter in the documentation and since it isn’t clear whether an alternative solution with pub struct OwningRef_<'t, O, T: ?Sized> {
owner: O,
reference: *const T,
marker: PhantomData<&'t T>,
}
type OwningRef<O, T: ?Sized> = OwningRef_<'static, O, T>;would be better (e.g. to reduce breakage). This would, effectlively, be like restricting And it’s not clear what the best choice for more vs. less lifetime parameters for all the type synonyms is. This PR so far took the approach of avoiding implicit |
| reference: *const T, | ||
| marker: PhantomData<&'t T>, |
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The standard library takes the approach to store this as a single reference &'t T in Ref:
https://github.com/rust-lang/rust/blob/5a8a44196b3cf099f8c9b0156bd902eaec0b4e5f/library/core/src/cell.rs#L1286-L1289
Although the lifetime is still not correct by itself and we'd still have to downgrade it like we do when it's stored in PhantomData, it looks like it would not break anything and be closer to what it should be (reference can't be null, the compiler knows it if specified this way and can perform optimization based on that knowledge).
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Actually that seems to have been an error by the std : https://github.com/rust-lang/rust/blob/ff8c8dfbe66701531e3e5e335c28c544d0fbc945/library/core/src/cell.rs#L1332-L1335
| reference: *mut T, | ||
| marker: PhantomData<&'t T>, |
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The standard library takes the approach to store this as a single reference &'t mut T in RefMut:
https://github.com/rust-lang/rust/blob/5a8a44196b3cf099f8c9b0156bd902eaec0b4e5f/library/core/src/cell.rs#L1662-L1665
Although the lifetime is still not correct by itself and we'd still have to downgrade it like we do when it's stored in PhantomData, it looks like it would not break anything and be closer to what it should be (reference can't be null, the compiler knows it if specified this way and can perform optimization based on that knowledge).
Resolves #71.