Effective C++ Ed. 3rd: Item 27. Minimise casting

Instead of "old" C style casts:

(T) expression             // cast expression to be of type T 
T(expression)           // cast expression to be of type T

Prefer C++ style-casts:

1. const_cast: To convert const datatype to non-const datatype.
2. reinterpret_cast: For low-level cast.
3. static_cast: to force implicit casts.
4. dynamic_cast: to perform safe-downcasting. For example:
   

   Derived *pd = new Derived();
   if ( Base *pb = dynamic_cast <   Base*  > pd )
       doSomething(); // returns true;
   if ( SuperDerived *pd2 = dynamic_cast <SuperDerived*> pd )
       doSomething(); // returns false; 

Following code compiles but doesn't run as you might expect:

class Window
{                                               // base class
public:
  virtual void onResize() { ... }   // base onResize impl  
...
};
class SpecialWindow: public Window {          // derived class
    virtual void onResize(){        // derived onResize impl;
    static_cast<Window>(*this).onResize();    // cast *this to Window,
                                              // then call its onResize;
                                              // this doesn't work!
    ...                                       // do SpecialWindow-
  }
                                           // specific stuff
  ...
};

Simply use

Window::onResize();

  instead of the line 9 above.

Note: Minimize use of casts, specially dynamic_cast.
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