refactor(data_structures): add PhantomData field to Stack and NonEmptyStack#15794
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…nEmptyStack` (#15794) Data structures which own `T`s should contain a `PhantomData<T>` field to signal to compiler the ownership semantics. For example `std::vec::Vec` does this. Add `PhantomData` field to `Stack` and `NonEmptyStack`. It's unclear to me if this is actually required for soundness or not. In the case of `std::vec::Vec`, it definitely is, but `Vec` uses `#[may_dangle]` in its `Drop` impl. Ideally we would use `#[may_dangle]` in these `Stack` types too, to loosen the borrow-checker's restrictions, but we're not able to as it's not available in stable Rust. Given that we're not using `#[may_dangle]`, maybe `PhantomData` is not required either, but it costs nothing, so it's better to be on safe side and add it.
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…nEmptyStack` (oxc-project#15794) Data structures which own `T`s should contain a `PhantomData<T>` field to signal to compiler the ownership semantics. For example `std::vec::Vec` does this. Add `PhantomData` field to `Stack` and `NonEmptyStack`. It's unclear to me if this is actually required for soundness or not. In the case of `std::vec::Vec`, it definitely is, but `Vec` uses `#[may_dangle]` in its `Drop` impl. Ideally we would use `#[may_dangle]` in these `Stack` types too, to loosen the borrow-checker's restrictions, but we're not able to as it's not available in stable Rust. Given that we're not using `#[may_dangle]`, maybe `PhantomData` is not required either, but it costs nothing, so it's better to be on safe side and add it.
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Data structures which own
Ts should contain aPhantomData<T>field to signal to compiler the ownership semantics. For examplestd::vec::Vecdoes this.Add
PhantomDatafield toStackandNonEmptyStack.It's unclear to me if this is actually required for soundness or not. In the case of
std::vec::Vec, it definitely is, butVecuses#[may_dangle]in itsDropimpl. Ideally we would use#[may_dangle]in theseStacktypes too, to loosen the borrow-checker's restrictions, but we're not able to as it's not available in stable Rust.Given that we're not using
#[may_dangle], maybePhantomDatais not required either, but it costs nothing, so it's better to be on safe side and add it.