New returns an initialized doubly linked list.

NewD returns an initialized doubly linked list.

NewDR returns an initialized doubly linked ring.

ListD defines a doubly linked list n <---> ..

ListDR defines a doubly linked list implemented using ring |-------------------------| root <--> n <---> ..

Node defines the node in a linked list.

NodeD defines the node in a doubly linked list.

NodeDR defines the node in a doubly linked list.

IList defines the linked list interface.