use alloc::rc::Rc;
use std::cell::RefCell;
use std::iter::{FusedIterator, IntoIterator};
#[derive(Debug)]
#[must_use = "iterator adaptors are lazy and do nothing unless consumed"]
pub struct RcIter<I> {
pub rciter: Rc<RefCell<I>>,
}
pub fn rciter<I>(iterable: I) -> RcIter<I::IntoIter>
where
I: IntoIterator,
{
RcIter {
rciter: Rc::new(RefCell::new(iterable.into_iter())),
}
}
impl<I> Clone for RcIter<I> {
clone_fields!(rciter);
}
impl<A, I> Iterator for RcIter<I>
where
I: Iterator<Item = A>,
{
type Item = A;
#[inline]
fn next(&mut self) -> Option<Self::Item> {
self.rciter.borrow_mut().next()
}
#[inline]
fn size_hint(&self) -> (usize, Option<usize>) {
(0, self.rciter.borrow().size_hint().1)
}
}
impl<I> DoubleEndedIterator for RcIter<I>
where
I: DoubleEndedIterator,
{
#[inline]
fn next_back(&mut self) -> Option<Self::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()
}
}
impl<A, I> FusedIterator for RcIter<I> where I: FusedIterator<Item = A> {}