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