File: issue-99551.rs

package info (click to toggle)
rustc-web 1.70.0%2Bdfsg1-7~deb11u1
  • links: PTS, VCS
  • area: main
  • in suites: bullseye
  • size: 1,517,036 kB
  • sloc: xml: 147,962; javascript: 10,210; sh: 8,590; python: 8,220; ansic: 5,901; cpp: 4,635; makefile: 4,006; asm: 2,856
file content (20 lines) | stat: -rw-r--r-- 399 bytes parent folder | download | duplicates (3) 
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
 
// build-pass
#![feature(trait_upcasting)]

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));
}