42 lines
698 B
Rust
42 lines
698 B
Rust
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//@ known-bug: #101557
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#![feature(generic_const_exprs)]
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use std::marker::PhantomData;
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trait Trait {
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const CONST: usize;
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}
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struct A<T: Trait> {
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_marker: PhantomData<T>,
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}
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impl<const N: usize> Trait for [i8; N] {
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const CONST: usize = N;
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}
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impl<const N: usize> From<usize> for A<[i8; N]> {
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fn from(_: usize) -> Self {
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todo!()
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}
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}
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impl<T: Trait> From<A<[i8; T::CONST]>> for A<T> {
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fn from(_: A<[i8; T::CONST]>) -> Self {
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todo!()
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}
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}
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fn f<T: Trait>() -> A<T>
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where
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[(); T::CONST]:,
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{
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// Usage of `0` is arbitrary
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let a = A::<[i8; T::CONST]>::from(0);
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A::<T>::from(a)
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}
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fn main() {
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// Usage of `1` is arbitrary
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f::<[i8; 1]>();
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}
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