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//@ run-pass
#![allow(unused_variables)]
// Check that a trait is still dyn-compatible (and usable) if it has
// generic methods so long as they require `Self : Sized`.
trait Counter {
fn tick(&mut self) -> u32;
fn with<F:FnOnce(u32)>(&self, f: F) where Self : Sized;
}
struct CCounter {
c: u32
}
impl Counter for CCounter {
fn tick(&mut self) -> u32 { self.c += 1; self.c }
fn with<F:FnOnce(u32)>(&self, f: F) { f(self.c); }
}
fn tick1<C:Counter>(c: &mut C) {
tick2(c);
c.with(|i| ());
}
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 };
tick1(&mut c);
assert_eq!(c.tick(), 3);
}
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