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[wxWidgets.git] / include / wx / weakref.h

diff --git a/include/wx/weakref.h b/include/wx/weakref.h
index 74b590d6278daff5c4c07298d373030b677301f2..08878903f48ada52804553a10c6c04c425a2b7bd 100644 (file)
--- a/include/wx/weakref.h
+++ b/include/wx/weakref.h
@@ -14,15 +14,17 @@
 #include "wx/tracker.h"
 
 
-// Some compilers (VC6, Borland, otehrs?) have problem with template specialization.
+// Some compilers (VC6, Borland, g++ < 3.3) have problem with template specialization.
 // However, this is only used for optimization purposes (a smaller wxWeakRef pointer)
-// (and the corner case of wxWeakRef<wxObject>). So for those compilers, we can fall 
-// back to the non-optimal case, where we use a the same type of weak ref (static one) 
+// (and the corner case of wxWeakRef<wxObject>). So for those compilers, we can fall
+// back to the non-optimal case, where we use a the same type of weak ref (static one)
 // in all cases. See defs.h for various setting these defines depending on compiler.
 
-#if !defined(HAVE_PARTIAL_SPECIALIZATION) || !defined(HAVE_TEMPLATE_OVERLOAD_RESOLUTION)
-    #define USE_ONLY_STATIC_WEAKREF 
-#endif 
+#if !defined(HAVE_PARTIAL_SPECIALIZATION) || \
+    !defined(HAVE_TEMPLATE_OVERLOAD_RESOLUTION) || \
+    (defined(__GNUC__) && !wxCHECK_GCC_VERSION(3, 3))
+    #define USE_ONLY_STATIC_WEAKREF
+#endif
 
 
 #ifndef USE_ONLY_STATIC_WEAKREF
@@ -59,6 +61,13 @@ public:
         }
     }
 
+    virtual void OnObjectDestroy()
+    {
+        // Tracked object itself removes us from list of trackers
+        wxASSERT(m_pobj != NULL);
+        m_pobj = NULL;
+    }
+
 protected:
     void Assign(T* pobj)
     {
@@ -82,13 +91,6 @@ protected:
         Assign( wr.m_pobj );
     }
 
-    virtual void OnObjectDestroy()
-    {
-        // Tracked object itself removes us from list of trackers
-        wxASSERT( m_pobj!=NULL );
-        m_pobj = NULL;
-    }
-
     T *m_pobj;
 };
 
@@ -122,6 +124,14 @@ struct wxWeakRefImpl<T, false> : public wxTrackerNode
         }
     }
 
+    virtual void OnObjectDestroy()
+    {
+        // Tracked object itself removes us from list of trackers
+        wxASSERT(m_pobj != NULL);
+        m_pobj = NULL;
+        m_ptbase = NULL;
+    }
+
 protected:
     wxWeakRefImpl() : m_pobj(NULL), m_ptbase(NULL) { }
 
@@ -139,7 +149,7 @@ protected:
         DoAssign( pobj, ptbase );
     }
 
-#ifdef HAVE_DYNAMIC_CAST
+#ifndef wxNO_RTTI
     void AssignHelper(T* pobj, wxInt2Type<false>)
     {
         // A last way to get a trackable pointer
@@ -155,7 +165,7 @@ protected:
             Release();
         }
     }
-#endif // HAVE_DYNAMIC_CAST
+#endif // RTTI enabled
 
     void AssignCopy(const wxWeakRefImpl& wr)
     {
@@ -177,14 +187,6 @@ protected:
         }
     }
 
-    virtual void OnObjectDestroy()
-    {
-        // Tracked object itself removes us from list of trackers
-        wxASSERT( m_pobj!=NULL );
-        m_pobj = NULL;
-        m_ptbase = NULL;
-    }
-
     T *m_pobj;
     wxTrackable *m_ptbase;
 };
@@ -200,13 +202,26 @@ class wxWeakRef : public
 #ifdef USE_ONLY_STATIC_WEAKREF
                   wxWeakRefStatic<T>
 #else
-                  wxWeakRefImpl<T, wxIsStaticTrackable<T>::value>
+                  wxWeakRefImpl<T, wxIsStaticTrackable<T>::value != 0>
 #endif
 {
 public:
+    typedef T element_type;
+
     // Default ctor
     wxWeakRef() { }
 
+    // Enabling this ctor for VC6 results in mysterious compilation failures in
+    // wx/window.h when assigning wxWindow pointers (FIXME-VC6)
+#ifndef __VISUALC6__
+    // Ctor from the object of this type: this is needed as the template ctor
+    // below is not used by at least g++4 when a literal NULL is used
+    wxWeakRef(T *pobj)
+    {
+        Assign(pobj);
+    }
+#endif // !__VISUALC6__
+
     // When we have the full type here, static_cast<> will always work
     // (or give a straight compiler error).
     template <class TDerived>
@@ -215,19 +230,12 @@ public:
         Assign(pobj);
     }
 
-    // We need this copy ctor, since otherwise a default compiler (binary) copy 
+    // We need this copy ctor, since otherwise a default compiler (binary) copy
     // happens (if embedded as an object member).
     wxWeakRef(const wxWeakRef<T>& wr)
     {
         Assign(wr.get());
     }
-    
-    template <class TDerived>
-    wxWeakRef<T>& operator=(TDerived* pobj)
-    {
-        this->Assign(pobj);
-        return *this;
-    }
 
     wxWeakRef<T>& operator=(const wxWeakRef<T>& wr)
     {
@@ -246,7 +254,7 @@ public:
 };
 
 
-#ifdef HAVE_DYNAMIC_CAST
+#ifndef wxNO_RTTI
 
 // Weak ref implementation assign objects are queried for wxTrackable
 // using dynamic_cast<>
@@ -265,18 +273,18 @@ public:
     {
         Assign(wr.get());
     }
-    
+
     virtual ~wxWeakRefDynamic() { Release(); }
 
     // Smart pointer functions
     T& operator*() const    { wxASSERT(m_pobj); return *m_pobj; }
     T* operator->() const   { wxASSERT(m_pobj); return m_pobj; }
-    
+
     T* get() const          { return m_pobj; }
     operator T* () const    { return m_pobj; }
 
     T* operator = (T* pobj) { Assign(pobj); return m_pobj; }
-    
+
     // Assign from another weak ref, point to same object
     T* operator = (const wxWeakRef<T> &wr) { Assign( wr.get() ); return m_pobj; }
 
@@ -293,6 +301,13 @@ public:
         }
     }
 
+    virtual void OnObjectDestroy()
+    {
+        wxASSERT_MSG(m_pobj, "tracked object should have removed us itself");
+
+        m_pobj = NULL;
+    }
+
 protected:
     void Assign(T *pobj)
     {
@@ -320,17 +335,10 @@ protected:
         }
     }
 
-    virtual void OnObjectDestroy()
-    {
-        wxASSERT_MSG( m_pobj, "tracked object should have removed us itself" );
-
-        m_pobj = NULL;
-    }
-
     T *m_pobj;
 };
 
-#endif // #ifdef HAVE_DYNAMIC_CAST
+#endif // RTTI enabled
 
 
 // Provide some basic types of weak references