flower/pcursor.hh

   1
   2 /*
   3   pcursor.hh -- part of flowerlib
   4
   5   (c) 1996 Han-Wen Nienhuys&Jan Nieuwenhuizen
   6 */
   7
   8 #ifndef PCURSOR_HH
   9 #define PCURSOR_HH
  10
  11
  12 /// cursor to go with PointerList
  13 template<class T>
  14 struct PCursor : private Cursor<void *> {
  15     friend class IPointerList<T>;
  16
  17     /// delete contents
  18     void junk();
  19 public:
  20     Cursor<void*>::ok;
  21     Cursor<void*>::del;
  22     Cursor<void*>::backspace;
  23     T get() {
  24         T p = ptr();
  25         Cursor<void*>::del();
  26         return p;
  27     }
  28     T get_prev() {
  29         (*this)--;
  30         return get();
  31     }
  32
  33     PointerList<T> &list() { return (PointerList<T>&)Cursor<void*>::list(); }
  34     PCursor<T> operator++(int) { return Cursor<void*>::operator++(0);}
  35     PCursor<T> operator--(int) { return Cursor<void*>::operator--(0); }
  36     PCursor<T> operator+=(int i) { return Cursor<void*>::operator+=(i);}
  37     PCursor<T> operator-=(int i) { return Cursor<void*>::operator-=(i); }
  38     PCursor<T> operator -(int no) const { return Cursor<void*>::operator-(no);}
  39     int operator -(PCursor<T> op) const { return Cursor<void*>::operator-(op);}
  40     PCursor<T> operator +( int no) const {return Cursor<void*>::operator+(no);}    PCursor(const PointerList<T> & l) : Cursor<void*> (l) {}
  41
  42     PCursor( const Cursor<void*>& cursor ) : Cursor<void*>(cursor) { }
  43     void* vptr() const { return  * ((Cursor<void*> &) *this); }
  44
  45     // should return T& ?
  46     T ptr() const { return (T) vptr(); }
  47     T operator ->() const { return  ptr(); }
  48     operator T() { return ptr(); }
  49     T operator *() { return ptr(); }
  50     void add(const T& p ) { Cursor<void*>::add((void*) p); }
  51     void insert(const T& p ) { Cursor<void*>::insert((void*) p);}
  52     static int compare(PCursor<T> a,PCursor<T>b) {
  53         return Cursor<void*>::compare(a,b);
  54     }
  55 };
  56 /**
  57   don't create PointerList<void*>'s.
  58   This cursor is just an interface class for Cursor. It takes care of the
  59   appropriate type casts
  60  */
  61
  62
  63
  64 #include "compare.hh"
  65 template_instantiate_compare(PCursor<T>, PCursor<T>::compare, template<class T>);
  66
  67 #endif