world: use list_for_each()

src/core/list.h

@@ -46,4 +46,7 @@ namespace list
 
 } // namespace list
 
+#define list_for_each(cur, head)                             \
+	for (cur = (head)->next; cur != (head); cur = cur->next)
+
 } // namespace crown

src/world/unit_manager.cpp

@@ -75,12 +75,11 @@ void UnitManager::unregister_destroy_callback(UnitDestroyCallback* udc)
 
 void UnitManager::trigger_destroy_callbacks(UnitId id)
 {
-	ListNode* cur = _callbacks.node.next;
-	while (cur != &_callbacks.node)
+	ListNode* cur;
+	list_for_each(cur != &_callbacks.node)
 	{
 		UnitDestroyCallback* udc = (UnitDestroyCallback*)container_of(cur, UnitDestroyCallback, node);
 		udc->destroy(id, udc->user_data);
-		cur = cur->next;
 	}
 }
 

src/world/world.cpp

@@ -66,11 +66,10 @@ World::World(Allocator& a, ResourceManager& rm, ShaderManager& sm, MaterialManag
 World::~World()
 {
 	// Destroy loaded levels
-	ListNode* cur = _levels.next;
-	while (cur != &_levels)
+	ListNode* cur;
+	list_for_each(cur != &_levels)
 	{
 		Level* level = (Level*)container_of(cur, Level, _node);
-		cur = cur->next;
 		CE_DELETE(*_allocator, level);
 	}