Peter, > On 14 Apr 2015, at 13:52, Peter Uhnák <i.uh...@gmail.com> wrote: > > I was surprised to learn that DoubleLinkedList is descendant of Object, while > LinkedList is descendant of SequencableCollection. Is there a particular > reason behind this? Are they really so conceptually different that DLL is not > even considered a collection? > > Thanks, > Peter
DoubleLinkedList was added to help the implementation of [LRU|TTL]Cache. It was kept small and independent. Inheriting from [Sequenceable]Collection is a larger responsibility, entails more requirements. I would not be against this, although I am not 100% sure it is easy (some methods return the link nodes, not the elements, a distinction unknown to collections in general - LinkedList is a bit ugly in this respect too). In any case, it would have to be supported by enough tests. It could be a nice project for Pharo 5. Sven
