73     pub(crate) fn pop_back(&mut self) -> Option<T> {  in pop_back()
160     pub(crate) fn back(&self) -> Option<&T> {  in back()
170     pub(crate) fn back_mut(&mut self) -> Option<&mut T> {  in back_mut()
181     pub(crate) fn back_node(&self) -> Option<&Node<T>> {  in back_node()
192     pub(crate) fn back_node_mut(&mut self) -> Option<&mut Node<T>> {  in back_node_mut()
311     pub(crate) fn remove_self(&mut self) -> Option<T> {  in remove_self()
334     fn next(&mut self) -> Option<&'a T> {  in next()
346     fn size_hint(&self) -> (usize, Option<usize>) {  in size_hint()
352     fn last(mut self) -> Option<&'a T> {  in last()
359     fn next_back(&mut self) -> Option<&'a T> {  in next_back()
383     fn next(&mut self) -> Option<&'a mut T> {  in next()
395     fn size_hint(&self) -> (usize, Option<usize>) {  in size_hint()
401     fn last(mut self) -> Option<&'a mut T> {  in last()
409     fn next_back(&mut self) -> Option<&'a mut T> {  in next_back()
433     pub(crate) fn index(&self) -> Option<usize> {  in index()
467     pub(crate) fn current(&self) -> Option<&'a T> {  in current()
477     pub(crate) fn current_node(&self) -> Option<&'a Node<T>> {  in current_node()
501     pub(crate) fn index(&self) -> Option<usize> {  in index()
536     pub(crate) fn current(&mut self) -> Option<&mut T> {  in current()
546     pub(crate) fn current_node(&mut self) -> Option<&'a mut Node<T>> {  in current_node()
560     pub(crate) fn remove_current(&mut self) -> Option<T> {  in remove_current()