| // Copyright 2017 The Rust Project Developers. See the COPYRIGHT |
| // file at the top-level directory of this distribution and at |
| // http://rust-lang.org/COPYRIGHT. |
| // |
| // Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or |
| // http://www.apache.org/licenses/LICENSE-2.0> or the MIT license |
| // <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your |
| // option. This file may not be copied, modified, or distributed |
| // except according to those terms. |
| |
| #![allow(const_err)] |
| |
| trait Foo { |
| const AMT: usize; |
| } |
| |
| enum Bar<A, B> { |
| First(A), |
| Second(B), |
| } |
| |
| impl<A: Foo, B: Foo> Foo for Bar<A, B> { |
| const AMT: usize = [A::AMT][(A::AMT > B::AMT) as usize]; |
| } |
| |
| impl Foo for u8 { |
| const AMT: usize = 1; |
| } |
| |
| impl Foo for u16 { |
| const AMT: usize = 2; |
| } |
| |
| fn main() { |
| println!("{}", <Bar<u16, u8> as Foo>::AMT); |
| //~^ ERROR erroneous constant used |
| //~| ERROR E0080 |
| } |