1 // Test if the on_unimplemented message override works
3 #![feature(rustc_attrs)]
6 #[rustc_on_unimplemented = "invalid"]
7 trait Index<Idx: ?Sized> {
9 fn index(&self, index: Idx) -> &Self::Output;
12 #[rustc_on_unimplemented = "a usize is required to index into a slice"]
13 impl Index<usize> for [i32] {
15 fn index(&self, index: usize) -> &i32 {
22 Index::<u32>::index(&[1, 2, 3] as &[i32], 2u32);