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Additional bounds are required for const generics using associated constants #80976
Description
Example below. Based on the description in #76560, I'd expect to not be required to add [(); From::DIM]: and [(); To::DIM] bounds to Transform because the associated consts are inherent to the trait's definition and thus are public APIs.
#![feature(generic_const_exprs)]
trait Vector {
type Scalar;
const DIM: usize;
}
struct Transform<From, To>
where
From: Vector,
To: Vector<Scalar = From::Scalar>,
{
columns: [[From::Scalar; From::DIM]; To::DIM],
}Reacted by Mark LeMoine, Adam Gausmann, Gurtej Kanwar and Trevor Gross
Activity
camelid commentedon Jan 17, 2021
It seemsEDIT: actually it is required :)const_evaluatable_checkedis not required to repro?lcnr commentedon Jun 24, 2022
triaged in https://rust-lang.zulipchat.com/#narrow/stream/260443-project-const-generics/topic/.60F-generic_const_exprs.60.20triage/near/287323105, if we want const evaluatable bounds this error is expected (though with a better error message). Whether these bounds are needed is tracked in rust-lang/project-const-generics#41