blob: f498718310d82e339af34ae38b9fa3884dab2648 (
plain)
| 1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
 | //@ build-pass
pub trait A {}
pub trait B {}
pub trait C: A + B {}
impl<X: A + B> C for X {}
pub fn test<'a, T>(view: T) -> Option<&'a mut dyn B>
where
    T: IntoIterator<Item = &'a mut dyn B>,
{
    return Some(view.into_iter().next().unwrap());
}
fn main() {
    let mut a: Vec<Box<dyn C>> = Vec::new();
    test(a.iter_mut().map(|c| c.as_mut() as &mut dyn B));
}
 |