rust/tests/ui/copy_iterator.rs

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Rust
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2018-07-28 17:34:52 +02:00
#![warn(clippy::copy_iterator)]
2018-07-17 19:22:55 +02:00
#[derive(Copy, Clone)]
struct Countdown(u8);
impl Iterator for Countdown {
type Item = u8;
fn next(&mut self) -> Option<u8> {
self.0.checked_sub(1).map(|c| {
self.0 = c;
c
})
}
}
fn main() {
let my_iterator = Countdown(5);
let a: Vec<_> = my_iterator.take(1).collect();
assert_eq!(a.len(), 1);
let b: Vec<_> = my_iterator.collect();
assert_eq!(b.len(), 5);
}