BidirectionalIterator<E> constructor Null safety

1. Dart
2. dart:core
3. BidirectionalIterator<E>
4. BidirectionalIterator constructor

BidirectionalIterator class

1. Constructors
2. BidirectionalIterator
3. Properties
4. current
5. hashCode
6. runtimeType
7. Methods
8. moveNext
9. movePrevious
10. noSuchMethod
11. toString
12. Operators
13. operator ==