File: upcast_reorder.rs

package info (click to toggle)
rustc 1.85.0%2Bdfsg3-1
  • links: PTS, VCS
  • area: main
  • in suites: experimental, sid, trixie
  • size: 893,396 kB
  • sloc: xml: 158,127; python: 35,830; javascript: 19,497; cpp: 19,002; sh: 17,245; ansic: 13,127; asm: 4,376; makefile: 1,051; perl: 29; lisp: 29; ruby: 19; sql: 11
file content (29 lines) | stat: -rw-r--r-- 460 bytes parent folder | download | duplicates (2) 
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
 
//@ run-pass
//
// issue: <https://github.com/rust-lang/rust/issues/131813>

#![feature(trait_upcasting)]

trait Pollable {
    #[allow(unused)]
    fn poll(&self) {}
}
trait FileIo: Pollable + Send + Sync {
    fn read(&self) {}
}
trait Terminal: Send + Sync + FileIo {}

struct A;

impl Pollable for A {}
impl FileIo for A {}
impl Terminal for A {}

fn main() {
    let a = A;

    let b = &a as &dyn Terminal;
    let c = b as &dyn FileIo;

    c.read();
}