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use std::iter::IntoIterator;
use std::rc::Rc;
use std::cell::RefCell;
pub struct RcIter<I> {
pub rciter: Rc<RefCell<I>>,
}
impl<I> RcIter<I>
{
pub fn new(iter: I) -> RcIter<I>
{
RcIter{rciter: Rc::new(RefCell::new(iter))}
}
}
impl<I> Clone for RcIter<I>
{
#[inline]
fn clone(&self) -> RcIter<I> {
RcIter{rciter: self.rciter.clone()}
}
}
impl<A, I> Iterator for RcIter<I> where
I: Iterator<Item=A>,
{
type Item = A;
#[inline]
fn next(&mut self) -> Option<A>
{
self.rciter.borrow_mut().next()
}
#[inline]
fn size_hint(&self) -> (usize, Option<usize>) {
let (_, hi) = self.rciter.borrow().size_hint();
(0, hi)
}
}
impl<I> DoubleEndedIterator for RcIter<I> where
I: DoubleEndedIterator,
{
#[inline]
fn next_back(&mut self) -> Option<I::Item>
{
self.rciter.borrow_mut().next_back()
}
}
impl<'a, I> IntoIterator for &'a RcIter<I> where
I: Iterator,
{
type Item = I::Item;
type IntoIter = RcIter<I>;
fn into_iter(self) -> RcIter<I>
{
self.clone()
}
}