30 lines
592 B
Rust
30 lines
592 B
Rust
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#![feature(specialization)]
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#![allow(incomplete_features)]
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pub trait ReflectDrop {
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const REFLECT_DROP: bool = false;
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}
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impl<T> ReflectDrop for T where T: Clone {}
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pub trait PinDropInternal {
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fn is_valid()
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where
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Self: ReflectDrop;
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}
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struct Bears<T>(T);
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default impl<T> ReflectDrop for Bears<T> {}
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impl<T: Sized> PinDropInternal for Bears<T> {
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fn is_valid()
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where
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Self: ReflectDrop,
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{
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let _ = [(); 0 - !!(<Bears<T> as ReflectDrop>::REFLECT_DROP) as usize]; //~ ERROR constant expression depends on a generic parameter
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}
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}
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fn main() {}
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