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use nonempty::NonEmpty;
use super::Height;
#[derive(Debug)]
pub struct Iter<'a, T> {
chain: &'a NonEmpty<T>,
next: usize,
next_back: usize,
}
impl<'a, T> Iter<'a, T> {
pub fn new(chain: &'a NonEmpty<T>) -> Self {
Self {
chain,
next: 0,
next_back: chain.len(),
}
}
}
impl<'a, T> Iterator for Iter<'a, T> {
type Item = (Height, &'a T);
fn next(&mut self) -> Option<Self::Item> {
if self.next == self.next_back {
return None;
}
let height = self.next;
self.next += 1;
self.chain.get(height).map(|item| (height as Height, item))
}
}
impl<'a, T> DoubleEndedIterator for Iter<'a, T> {
fn next_back(&mut self) -> Option<Self::Item> {
if self.next_back == self.next {
return None;
}
self.next_back -= 1;
let height = self.next_back;
self.chain.get(height).map(|item| (height as Height, item))
}
}