\begingroup\parskip 0pt\baselineskip 0pt\tt {\tt\obeyspaces\gdef {\hskip.5em}} \def\par{\leavevmode\endgraf} \catcode`\`=\active\obeylines \ttverbatimtypedef ... seq_impl_item;class seq_impl  { virtual int  cmp(GenPtr, GenPtr) const = 0; virtual int  int_type()          const = 0; virtual void clear_key(GenPtr&)  const = 0; virtual void clear_inf(GenPtr&)  const = 0; virtual void copy_key(GenPtr&)   const = 0; virtual void copy_inf(GenPtr&)   const = 0;public: seq_impl(); seq_impl(const seq_impl&);~seq_impl(); seq_impl& operator=(const seq_impl&); seq_impl& conc(seq_impl&);  seq_impl_item insert(GenPtr,GenPtr); seq_impl_item insert_at_item(seq_impl_item,GenPtr,GenPtr); seq_impl_item lookup(GenPtr)      const; seq_impl_item locate(GenPtr)      const; seq_impl_item locate_pred(GenPtr) const; seq_impl_item succ(seq_impl_item) const; seq_impl_item pred(seq_impl_item) const; seq_impl_item item(void* p) const { return seq_impl_item(p); }  GenPtr key(seq_impl_item) const; GenPtr inf(seq_impl_item) const;  void del(GenPtr);  void del_item(seq_impl_item);  void change_inf(seq_impl_item,GenPtr); void split_at_item(seq_impl_item,seq_impl&,seq_impl&); void reverse_items(seq_impl_item,seq_impl_item);  void clear();  int  size()  const;};\endgroup