diff options
Diffstat (limited to 'src/test/ui/const-generics/issues/issue-83288.rs')
-rw-r--r-- | src/test/ui/const-generics/issues/issue-83288.rs | 69 |
1 files changed, 69 insertions, 0 deletions
diff --git a/src/test/ui/const-generics/issues/issue-83288.rs b/src/test/ui/const-generics/issues/issue-83288.rs new file mode 100644 index 000000000..a24596d24 --- /dev/null +++ b/src/test/ui/const-generics/issues/issue-83288.rs @@ -0,0 +1,69 @@ +// build-pass + +#![allow(incomplete_features)] +#![feature(generic_const_exprs)] + +use std::{marker::PhantomData, ops::Mul}; + +pub enum Nil {} +pub struct Cons<T, L> { + _phantom: PhantomData<(T, L)>, +} + +pub trait Indices<const N: usize> { + const RANK: usize; + const NUM_ELEMS: usize; +} + +impl<const N: usize> Indices<N> for Nil { + const RANK: usize = 0; + const NUM_ELEMS: usize = 1; +} + +impl<T, I: Indices<N>, const N: usize> Indices<N> for Cons<T, I> { + const RANK: usize = I::RANK + 1; + const NUM_ELEMS: usize = I::NUM_ELEMS * N; +} + +pub trait Concat<J> { + type Output; +} + +impl<J> Concat<J> for Nil { + type Output = J; +} + +impl<T, I, J> Concat<J> for Cons<T, I> +where + I: Concat<J>, +{ + type Output = Cons<T, <I as Concat<J>>::Output>; +} + +pub struct Tensor<I: Indices<N>, const N: usize> +where + [u8; I::NUM_ELEMS]: Sized, +{ + pub data: [u8; I::NUM_ELEMS], + _phantom: PhantomData<I>, +} + +impl<I: Indices<N>, J: Indices<N>, const N: usize> Mul<Tensor<J, N>> for Tensor<I, N> +where + I: Concat<J>, + <I as Concat<J>>::Output: Indices<N>, + [u8; I::NUM_ELEMS]: Sized, + [u8; J::NUM_ELEMS]: Sized, + [u8; <I as Concat<J>>::Output::NUM_ELEMS]: Sized, +{ + type Output = Tensor<<I as Concat<J>>::Output, N>; + + fn mul(self, _rhs: Tensor<J, N>) -> Self::Output { + Tensor { + data: [0u8; <I as Concat<J>>::Output::NUM_ELEMS], + _phantom: PhantomData, + } + } +} + +fn main() {} |