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//@ run-pass
#![allow(unused_mut)]
// Check that a trait is still dyn-compatible (and usable) if it has
// methods with by-value self so long as they require `Self : Sized`.
trait Counter {
fn tick(&mut self) -> u32;
fn get(self) -> u32 where Self : Sized;
}
struct CCounter {
c: u32
}
impl Counter for CCounter {
fn tick(&mut self) -> u32 { self.c += 1; self.c }
fn get(self) -> u32 where Self : Sized { self.c }
}
fn tick1<C:Counter>(mut c: C) -> u32 {
tick2(&mut c);
c.get()
}
fn tick2(c: &mut dyn Counter) {
tick3(c);
}
fn tick3<C:?Sized+Counter>(c: &mut C) {
c.tick();
c.tick();
}
fn main() {
let mut c = CCounter { c: 0 };
let value = tick1(c);
assert_eq!(value, 2);
}
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