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//@ run-pass
// Tests for RFC 1268: we allow overlapping impls of marker traits,
// that is, traits with #[marker]. In this case, a type `T` is
// `MyMarker` if it is either `Debug` or `Display`.
#![feature(marker_trait_attr)]
use std::fmt::{Debug, Display};
#[marker]
trait MyMarker {}
impl<T: Debug> MyMarker for T {}
impl<T: Display> MyMarker for T {}
fn foo<T: MyMarker>(t: T) -> T {
t
}
fn main() {
// Debug && Display:
assert_eq!(1, foo(1));
assert_eq!(2.0, foo(2.0));
// Debug && !Display:
assert_eq!(vec![1], foo(vec![1]));
}
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