mirror of https://github.com/rust-lang/rust
45 lines
807 B
Rust
45 lines
807 B
Rust
//@ run-pass
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trait Foo {
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const X: i32;
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fn get_x() -> i32 {
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Self::X
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}
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}
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struct Abc;
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impl Foo for Abc {
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const X: i32 = 11;
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}
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struct Def;
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impl Foo for Def {
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const X: i32 = 97;
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}
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struct Proxy<T>(#[allow(dead_code)] T);
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impl<T: Foo> Foo for Proxy<T> {
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const X: i32 = T::X;
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}
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fn sub<A: Foo, B: Foo>() -> i32 {
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A::X - B::X
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}
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trait Bar: Foo { //~ WARN trait `Bar` is never used
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const Y: i32 = Self::X;
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}
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fn main() {
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assert_eq!(11, Abc::X);
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assert_eq!(97, Def::X);
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assert_eq!(11, Abc::get_x());
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assert_eq!(97, Def::get_x());
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assert_eq!(-86, sub::<Abc, Def>());
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assert_eq!(86, sub::<Def, Abc>());
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assert_eq!(-86, sub::<Proxy<Abc>, Def>());
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assert_eq!(-86, sub::<Abc, Proxy<Def>>());
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assert_eq!(86, sub::<Proxy<Def>, Proxy<Abc>>());
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}
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