1 class Widget{
 2 public:
 3 Widget();
 4 virtual ~Widget();
 5 virtual size_t size() const;
 6 virtual void normalize();
 7 void swap(Widget& other);
 8 ...
 9 };
10 
11 
12 void doProcessing(Widget& w)
13 {
14     if(w.size() > 10 && w != someWW)
15     {
16         Widget temp(w);
17         temp.normalize();
18         temp.swap(w);
19     }
20 }

 1 template<typename T>
 2 void doProcessing(T& w)
 3 {
 4     if(w.size() > 10 && w != someWW)
 5     {
 6          T temp(w);
 7          temp.normalize();
 8          temp.swap(w);
 9     }
10 }