32 lines
481 B
Rust
32 lines
481 B
Rust
|
// check-pass
|
||
|
|
#![feature(specialization)]
|
||
|
|
|
||
|
|
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!()
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
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();
|
||
|
|
}
|