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//@ check-pass
#![feature(specialization)] //~ WARN the feature `specialization` is incomplete
pub struct Cloned<I>(I);
impl<'a, I, T: 'a> Iterator for Cloned<I>
where
I: Iterator<Item = &'a T>,
T: Clone,
{
type Item = T;
fn next(&mut self) -> Option<T> {
unimplemented!()
}
default fn count(self) -> usize where Self: Sized {
self.fold(0, |cnt, _| cnt + 1)
}
}
impl<'a, I, T: 'a> Iterator for Cloned<I>
where
I: Iterator<Item = &'a T>,
T: Copy,
{
fn count(self) -> usize {
unimplemented!()
}
}
fn main() {
let a = [1,2,3,4];
Cloned(a.iter()).count();
}
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