flower/plist.hh

   1 /*
   2   list.hh -- part of flowerlib
   3
   4   (c) 1996 Han-Wen Nienhuys & Jan Nieuwenhuizen
   5 */
   6
   7 #ifndef PLIST_HH
   8 #define PLIST_HH
   9
  10 #include "list.hh"
  11
  12 /**
  13   A list of pointers.
  14
  15   Use for list of pointers, e.g. PointerList<AbstractType*>.
  16   This class does no deletion of the pointers, but it knows how to
  17   copy itself (shallow copy). We could have derived it from List<T>,
  18   but this design saves a lot of code dup; for all PointerLists in the
  19   program only one parent List<void*> is instantiated.
  20   */
  21 template<class T>
  22 class PointerList : public List<void *>
  23 {
  24  public:
  25     PCursor<T> top() const{
  26         return PCursor<T> (List<void*>::top());
  27     }
  28     PCursor<T> bottom() const {
  29         return PCursor<T> (List<void*>::bottom());
  30     }
  31     PCursor<T> find(T) const;
  32     void concatenate(PointerList<T> const &s) { List<void*>::concatenate(s); }
  33     PointerList() {}
  34 };
  35
  36 /**   PointerList which deletes pointers given to it.
  37   NOTE:
  38
  39   The copy constructor doesn't do what you'd want:
  40   Since T might have a virtual ctor, we don't try to do a
  41
  42     new T(*cursor)
  43
  44   You have to copy this yourself, or use the macro PointerList__copy
  45
  46   */
  47 template<class T>
  48 class IPointerList : public PointerList<T> {
  49 public:
  50     IPointerList(const IPointerList&) { set_empty(); }
  51     IPointerList() { }
  52     ~IPointerList();
  53 };
  54
  55 #define IPointerList__copy(T, to, from, op)   \
  56   for (PCursor<T> _pc_(from); _pc_.ok(); _pc_++)\
  57       to.bottom().add(_pc_->op)\
  58   \
  59
  60
  61 template<class T>
  62 void PL_copy(IPointerList<T*> &dst,IPointerList<T*> const&src);
  63
  64
  65 #define PL_instantiate(a)  template class PointerList<a*>; \
  66         template class PCursor<a*>;
  67 #define IPL_instantiate(a) PL_instantiate(a); \
  68         template class IPointerList<a*>
  69
  70 #include "plist.inl"
  71
  72 #endif