| // check-pass | |
| struct D; | |
| trait Tr { | |
| type It; | |
| fn foo(self) -> Option<Self::It>; | |
| } | |
| impl<'a> Tr for &'a D { | |
| type It = (); | |
| fn foo(self) -> Option<()> { None } | |
| } | |
| fn run<F>(f: F) | |
| where for<'a> &'a D: Tr, | |
| F: Fn(<&D as Tr>::It), | |
| { | |
| let d = &D; | |
| while let Some(i) = d.foo() { | |
| f(i); | |
| } | |
| } | |
| fn main() { | |
| run(|_| {}); | |
| } |