rust/tests/ui/traits/inheritance/diamond.rs
2024-02-16 20:02:50 +00:00

29 lines
661 B
Rust

//@ run-pass
#![allow(dead_code)]
// B and C both require A, so D does as well, twice, but that's just fine
trait A { fn a(&self) -> isize; }
trait B: A { fn b(&self) -> isize; }
trait C: A { fn c(&self) -> isize; }
trait D: B + C { fn d(&self) -> isize; }
struct S { bogus: () }
impl A for S { fn a(&self) -> isize { 10 } }
impl B for S { fn b(&self) -> isize { 20 } }
impl C for S { fn c(&self) -> isize { 30 } }
impl D for S { fn d(&self) -> isize { 40 } }
fn f<T:D>(x: &T) {
assert_eq!(x.a(), 10);
assert_eq!(x.b(), 20);
assert_eq!(x.c(), 30);
assert_eq!(x.d(), 40);
}
pub fn main() {
let value = &S { bogus: () };
f(value);
}