| #![feature(adt_const_params)] | |
| //~^ WARN the feature `adt_const_params` is incomplete and may not be safe to use and/or cause compiler crashes [incomplete_features] | |
| #[derive(PartialEq, Eq)] | |
| enum Nat { | |
| Z, | |
| S(Box<Nat>), | |
| } | |
| fn foo<const N: Nat>() {} | |
| //~^ ERROR `Nat` must implement `ConstParamTy` to be used as the type of a const generic parameter | |
| fn main() {} |