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//@ run-pass
#![feature(trait_upcasting)]
trait Foo<T: Default + ToString>: Bar<i32> + Bar<T> {}
trait Bar<T: Default + ToString> {
fn bar(&self) -> String {
T::default().to_string()
}
}
struct S1;
impl Bar<i32> for S1 {}
impl Foo<i32> for S1 {}
struct S2;
impl Bar<i32> for S2 {}
impl Bar<bool> for S2 {}
impl Foo<bool> for S2 {}
fn test1(x: &dyn Foo<i32>) {
let s = x as &dyn Bar<i32>;
assert_eq!("0", &s.bar().to_string());
}
fn test2(x: &dyn Foo<bool>) {
let p = x as &dyn Bar<i32>;
assert_eq!("0", &p.bar().to_string());
let q = x as &dyn Bar<bool>;
assert_eq!("false", &q.bar().to_string());
}
fn main() {
let s1 = S1;
test1(&s1);
let s2 = S2;
test2(&s2);
}
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