| |
| pub trait IterUtilsExt : Iterator { |
| /// Return the first element that maps to `Some(_)`, or None if the iterator |
| /// was exhausted. |
| fn ex_find_map<F, R>(&mut self, mut f: F) -> Option<R> |
| where F: FnMut(Self::Item) -> Option<R> |
| { |
| for elt in self { |
| if let result @ Some(_) = f(elt) { |
| return result; |
| } |
| } |
| None |
| } |
| |
| /// Return the last element from the back that maps to `Some(_)`, or |
| /// None if the iterator was exhausted. |
| fn ex_rfind_map<F, R>(&mut self, mut f: F) -> Option<R> |
| where F: FnMut(Self::Item) -> Option<R>, |
| Self: DoubleEndedIterator, |
| { |
| while let Some(elt) = self.next_back() { |
| if let result @ Some(_) = f(elt) { |
| return result; |
| } |
| } |
| None |
| } |
| } |
| |
| impl<I> IterUtilsExt for I where I: Iterator { } |