46 lines
1.4 KiB
Rust
46 lines
1.4 KiB
Rust
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#![feature(derive_smart_pointer, arbitrary_self_types)]
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use std::marker::SmartPointer;
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#[derive(SmartPointer)]
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//~^ ERROR: `SmartPointer` can only be derived on `struct`s with `#[repr(transparent)]`
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enum NotStruct<'a, T: ?Sized> {
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Variant(&'a T),
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}
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#[derive(SmartPointer)]
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//~^ ERROR: At least one generic type should be designated as `#[pointee]` in order to derive `SmartPointer` traits
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#[repr(transparent)]
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struct NoPointee<'a, T: ?Sized> {
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ptr: &'a T,
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}
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#[derive(SmartPointer)]
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//~^ ERROR: `SmartPointer` can only be derived on `struct`s with at least one field
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#[repr(transparent)]
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struct NoField<'a, #[pointee] T: ?Sized> {}
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//~^ ERROR: lifetime parameter `'a` is never used
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//~| ERROR: type parameter `T` is never used
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#[derive(SmartPointer)]
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//~^ ERROR: `SmartPointer` can only be derived on `struct`s with at least one field
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#[repr(transparent)]
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struct NoFieldUnit<'a, #[pointee] T: ?Sized>();
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//~^ ERROR: lifetime parameter `'a` is never used
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//~| ERROR: type parameter `T` is never used
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#[derive(SmartPointer)]
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//~^ ERROR: `SmartPointer` can only be derived on `struct`s with `#[repr(transparent)]`
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struct NotTransparent<'a, #[pointee] T: ?Sized> {
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ptr: &'a T,
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}
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// However, reordering attributes should work nevertheless.
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#[repr(transparent)]
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#[derive(SmartPointer)]
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struct ThisIsAPossibleSmartPointer<'a, #[pointee] T: ?Sized> {
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ptr: &'a T,
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}
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fn main() {}
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