class interface DS_PAIR[G,H]

creation
   make (v: G; w: H)
      --  Create a new cell containing v and w.

      ensure
         first_set: first = v;
         second_set: second = w

feature(s) from DS_CELL
   --  Access

   first: G
      --  Content of cell


feature(s) from DS_CELL
   --  Element change

   put_first (v: G)
      --  Insert v in cell.

      ensure
         inserted: first = v

feature(s) from DS_CELL
   --  Element change

   make_first (v: G)
      --  Insert v in cell.

      ensure
         inserted: first = v

feature(s) from DS_PAIR
   --  Access

   second: H
      --  Second item of cell


feature(s) from DS_PAIR
   --  Element change

   put_second (w: H)
      --  Insert w in cell.

      ensure
         inserted: second = w


end of DS_PAIR[G,H]