Changeset 10568 for code/branches/core7/src/libraries/core/object/IteratorBase.h

Timestamp:

Sep 8, 2015, 10:02:46 PM (9 years ago)

Author:

landauf

Message:

Enforce type-safety of ObjectListIterator.
Previously it was possible to convert any ObjectListBaseElement* to an ObjectListIterator<T> with any T. This was because ObjectListIterator can be created from IteratorBase which in turn had a public constructor for ObjectListBaseElement*.
Now this constructor in IteratorBase is protected. As a replacement, there are two new public constructors for ObjectListElement<T>* either for the same class T or another class O that must be a derivative of T.
In short, this means that this is ok:

ObjectList<BaseObject>::iterator it = ObjectList<BaseObject>::begin(); ok, same class
ObjectList<BaseObject>::iterator it = ObjectList<WorldEntity>::begin(); ok, WorldEntity is derivative of BaseObject

But this will now fail to compile:

ObjectList<BaseObject>::iterator it = ObjectList<Listable>::begin(); not ok, Listable is not a derivative ob BaseObject

File:

• code/branches/core7/src/libraries/core/object/IteratorBase.h (modified) (1 diff)

code/branches/core7/src/libraries/core/object/IteratorBase.h

@@ -54 +54 @@
         BOOST_STATIC_ASSERT((boost::is_base_of<Listable, T>::value));
 
+        protected:
+            /**
+                @brief Constructor: Sets the element, whereon the iterator points, to the given element.
+                This constructor is protected and only for internal usage (don't mess with the BaseElements directly).
+            */
+            inline IteratorBase(ObjectListBaseElement* element = NULL)
+            {
+                this->element_ = element;
+                this->registerIterator();
+            }
+
+
         public:
             /**
-                @brief Constructor: Sets the element, whereon the iterator points, to zero.
-            */
-            inline IteratorBase(ObjectListBaseElement* element)
-            {
+                @brief Constructor: Sets the element, whereon the iterator points, to the given element.
+            */
+            inline IteratorBase(ObjectListElement<T>* element)
+            {
+                this->element_ = element;
+                this->registerIterator();
+            }
+
+            /**
+                @brief Constructor: Sets the element, whereon the iterator points, to the given element of another type.
+                The element's type O must be a derivative of the Iterator's type T.
+            */
+            template <class O>
+            inline IteratorBase(ObjectListElement<O>* element)
+            {
+                (void)static_cast<T*>((O*)NULL); // Check type: The element's type O must be a derivative of the Iterator's type T.
                 this->element_ = element;
                 this->registerIterator();