type4.hpp

C++ Templates 完全导引范例

/* The following code example is taken from the book
 * "C++ Templates - The Complete Guide"
 * by David Vandevoorde and Nicolai M. Josuttis, Addison-Wesley, 2002
 *
 * (C) Copyright David Vandevoorde and Nicolai M. Josuttis 2002.
 * Permission to copy, use, modify, sell and distribute this software
 * is granted provided this copyright notice appears in all copies.
 * This software is provided "as is" without express or implied
 * warranty, and with no claim as to its suitability for any purpose.
 */
#include <stddef.h>

template<typename T, size_t N>
class CompoundT <T[N]> {    // partial specialization for arrays
  public:
    enum { IsPtrT = 0, IsRefT = 0, IsArrayT = 1,
           IsFuncT = 0, IsPtrMemT = 0 };
    typedef T BaseT;
    typedef typename CompoundT<T>::BottomT BottomT;
    typedef CompoundT<void> ClassT;
};

template<typename T>
class CompoundT <T[]> {    // partial specialization for empty arrays
  public:
    enum { IsPtrT = 0, IsRefT = 0, IsArrayT = 1,
           IsFuncT = 0, IsPtrMemT = 0 };
    typedef T BaseT;
    typedef typename CompoundT<T>::BottomT BottomT;
    typedef CompoundT<void> ClassT;
};

template<typename T, typename C>
class CompoundT <T C::*> {  // partial specialization for pointer-to-members
  public:
    enum { IsPtrT = 0, IsRefT = 0, IsArrayT = 0,
           IsFuncT = 0, IsPtrMemT = 1 };
    typedef T BaseT;
    typedef typename CompoundT<T>::BottomT BottomT;
    typedef C ClassT;
};