RosettaCodeData/Task/Doubly-linked-list-Element-definition/Pascal/doubly-linked-list-element-definition.pas

type link_ptr = ^link;
     data_ptr = ^data; (* presumes that type 'data' is defined above *)
     link = record
              prev: link_ptr;
              next: link_ptr;
              data: data_ptr;
            end;