error: generic parameters may not be used in const operations
  --> $DIR/issue-62220.rs:7:59
   |
LL | pub type TruncatedVector<T, const N: usize> = Vector<T, { N - 1 }>;
   |                                                           ^ cannot perform const operation using `N`
   |
   = help: const parameters may only be used as standalone arguments, i.e. `N`
   = help: use `#![feature(const_generics)]` and `#![feature(const_evaluatable_checked)]` to allow generic const expressions

error: aborting due to previous error