functional

linux下编程用 编译软件

      // Retrieve a pointer to the function object
      static _Functor* _M_get_pointer(const _Any_data& __source)
      {
        const _Functor* __ptr =
          __stored_locally? &__source._M_access<_Functor>()
          /* have stored a pointer */ : __source._M_access<_Functor*>();
        return const_cast<_Functor*>(__ptr);
      }

      // Clone a location-invariant function object that fits within
      // an _Any_data structure.
      static void
      _M_clone(_Any_data& __dest, const _Any_data& __source, true_type)
      {
        new (__dest._M_access()) _Functor(__source._M_access<_Functor>());
      }

      // Clone a function object that is not location-invariant or
      // that cannot fit into an _Any_data structure.
      static void
      _M_clone(_Any_data& __dest, const _Any_data& __source, false_type)
      {
        __dest._M_access<_Functor*>() =
          new _Functor(*__source._M_access<_Functor*>());
      }

      // Destroying a location-invariant object may still require
      // destruction.
      static void
      _M_destroy(_Any_data& __victim, true_type)
      {
        __victim._M_access<_Functor>().~_Functor();
      }

      // Destroying an object located on the heap.
      static void
      _M_destroy(_Any_data& __victim, false_type)
      {
        delete __victim._M_access<_Functor*>();
      }

    public:
      static bool
      _M_manager(_Any_data& __dest, const _Any_data& __source,
                 _Manager_operation __op)
      {
        switch (__op) {
        case __get_type_info:
          __dest._M_access<const type_info*>() = &typeid(_Functor);
          break;

        case __get_functor_ptr:
          __dest._M_access<_Functor*>() = _M_get_pointer(__source);
          break;

        case __clone_functor:
          _M_clone(__dest, __source, _Local_storage());
          break;

        case __destroy_functor:
          _M_destroy(__dest, _Local_storage());
          break;
        }
        return false;
      }

      static void
      _M_init_functor(_Any_data& __functor, const _Functor& __f)
      {
        _M_init_functor(__functor, __f, _Local_storage());
      }

      template<typename _Signature>
      static bool
      _M_not_empty_function(const function<_Signature>& __f)
      {
        return __f;
      }

      template<typename _Tp>
      static bool
      _M_not_empty_function(const _Tp*& __fp)
      {
        return __fp;
      }

      template<typename _Class, typename _Tp>
      static bool
      _M_not_empty_function(_Tp _Class::* const& __mp)
      {
        return __mp;
      }

      template<typename _Tp>
      static bool
      _M_not_empty_function(const _Tp&)
      {
        return true;
      }

    private:
      static void
      _M_init_functor(_Any_data& __functor, const _Functor& __f, true_type)
      {
        new (__functor._M_access()) _Functor(__f);
      }

      static void
      _M_init_functor(_Any_data& __functor, const _Functor& __f, false_type)
      {
        __functor._M_access<_Functor*>() = new _Functor(__f);
      }
    };

    template<typename _Functor>
    class _Ref_manager : public _Base_manager<_Functor*>
    {
      typedef _Function_base::_Base_manager<_Functor*> _Base;

    public:
      static bool
      _M_manager(_Any_data& __dest, const _Any_data& __source,
                 _Manager_operation __op)
      {
        switch (__op) {
        case __get_type_info:
          __dest._M_access<const type_info*>() = &typeid(_Functor);
          break;

        case __get_functor_ptr:
          __dest._M_access<_Functor*>() = *_Base::_M_get_pointer(__source);
          return is_const<_Functor>::value;
          break;

        default:
          _Base::_M_manager(__dest, __source, __op);
        }
        return false;
      }

      static void
      _M_init_functor(_Any_data& __functor, reference_wrapper<_Functor> __f)
      {
        // TBD: Use address_of function instead
        _Base::_M_init_functor(__functor, &__f.get());
      }
    };

    _Function_base() : _M_manager(0) { }

    ~_Function_base()
    {
      if (_M_manager)
        {
          _M_manager(_M_functor, _M_functor, __destroy_functor);
        }
    }


    bool _M_empty() const { return !_M_manager; }

    typedef bool (*_Manager_type)(_Any_data&, const _Any_data&,
                                  _Manager_operation);

    _Any_data     _M_functor;
    _Manager_type _M_manager;
  };

  // [3.7.2.7] null pointer comparisons

  /**
   *  @brief Compares a polymorphic function object wrapper against 0
   *  (the NULL pointer).
   *  @returns @c true if the wrapper has no target, @c false otherwise
   *
   *  This function will not throw an exception.
   */
  template<typename _Signature>
    inline bool
    operator==(const function<_Signature>& __f, _M_clear_type*)
    {
      return !__f;
    }

  /**
   *  @overload
   */
  template<typename _Signature>
    inline bool
    operator==(_M_clear_type*, const function<_Signature>& __f)
    {
      return !__f;
    }

  /**
   *  @brief Compares a polymorphic function object wrapper against 0
   *  (the NULL pointer).
   *  @returns @c false if the wrapper has no target, @c true otherwise
   *
   *  This function will not throw an exception.
   */
  template<typename _Signature>
    inline bool
    operator!=(const function<_Signature>& __f, _M_clear_type*)
    {
      return __f;
    }

  /**
   *  @overload
   */
  template<typename _Signature>
    inline bool
    operator!=(_M_clear_type*, const function<_Signature>& __f)
    {
      return __f;
    }

  // [3.7.2.8] specialized algorithms

  /**
   *  @brief Swap the targets of two polymorphic function object wrappers.
   *
   *  This function will not throw an exception.
   */
  template<typename _Signature>
    inline void
    swap(function<_Signature>& __x, function<_Signature>& __y)
    {
      __x.swap(__y);
    }

#define _GLIBCXX_JOIN(X,Y) _GLIBCXX_JOIN2( X , Y )
#define _GLIBCXX_JOIN2(X,Y) _GLIBCXX_JOIN3(X,Y)
#define _GLIBCXX_JOIN3(X,Y) X##Y
#define _GLIBCXX_REPEAT_HEADER <tr1/functional_iterate.h>
#include <tr1/repeat.h>
#undef _GLIBCXX_REPEAT_HEADER
#undef _GLIBCXX_JOIN3
#undef _GLIBCXX_JOIN2
#undef _GLIBCXX_JOIN

  // Definition of default hash function std::tr1::hash<>.  The types for
  // which std::tr1::hash<T> is defined is in clause 6.3.3. of the PDTR.
  template<typename T>
    struct hash;

#define tr1_hashtable_define_trivial_hash(T)            \
  template<>                                            \
    struct hash<T>                                      \
    : public std::unary_function<T, std::size_t>        \
    {                                                   \
      std::size_t                                       \
      operator()(T val) const                           \
      { return static_cast<std::size_t>(val); }         \
    }                                                     

  tr1_hashtable_define_trivial_hash(bool);
  tr1_hashtable_define_trivial_hash(char);
  tr1_hashtable_define_trivial_hash(signed char);
  tr1_hashtable_define_trivial_hash(unsigned char);
  tr1_hashtable_define_trivial_hash(wchar_t);
  tr1_hashtable_define_trivial_hash(short);
  tr1_hashtable_define_trivial_hash(int);
  tr1_hashtable_define_trivial_hash(long);
  tr1_hashtable_define_trivial_hash(unsigned short);
  tr1_hashtable_define_trivial_hash(unsigned int);
  tr1_hashtable_define_trivial_hash(unsigned long);

#undef tr1_hashtable_define_trivial_hash

  template<typename T>
    struct hash<T*>
    : public std::unary_function<T*, std::size_t>
    {
      std::size_t
      operator()(T* p) const
      { return reinterpret_cast<std::size_t>(p); }
    };

  // Fowler / Noll / Vo (FNV) Hash (type FNV-1a)
  // (used by the next specializations of std::tr1::hash<>)

  // Dummy generic implementation (for sizeof(size_t) != 4, 8).
  template<std::size_t = sizeof(std::size_t)>
    struct Fnv_hash
    {
      static std::size_t
      hash(const char* first, std::size_t length)
      {
	std::size_t result = 0;
	for (; length > 0; --length)
	  result = (result * 131) + *first++;
	return result;
      }
    };

  template<>
    struct Fnv_hash<4>
    {
      static std::size_t
      hash(const char* first, std::size_t length)
      {
	std::size_t result = static_cast<std::size_t>(2166136261UL);
	for (; length > 0; --length)
	  {
	    result ^= (std::size_t)*first++;
	    result *= 16777619UL;
	  }
	return result;
      }
    };
  
  template<>
    struct Fnv_hash<8>
    {
      static std::size_t
      hash(const char* first, std::size_t length)
      {
	std::size_t result = static_cast<std::size_t>(14695981039346656037ULL);
	for (; length > 0; --length)
	  {
	    result ^= (std::size_t)*first++;
	    result *= 1099511628211ULL;
	  }
	return result;
      }
    };

  // XXX String and floating point hashes probably shouldn't be inline
  // member functions, since are nontrivial.  Once we have the framework
  // for TR1 .cc files, these should go in one.
  template<>
    struct hash<std::string>
    : public std::unary_function<std::string, std::size_t>
    {      
      std::size_t
      operator()(const std::string& s) const
      { return Fnv_hash<>::hash(s.data(), s.length()); }
    };

#ifdef _GLIBCXX_USE_WCHAR_T
  template<>
    struct hash<std::wstring>
    : public std::unary_function<std::wstring, std::size_t>
    {
      std::size_t
      operator()(const std::wstring& s) const
      {
	return Fnv_hash<>::hash(reinterpret_cast<const char*>(s.data()),
				s.length() * sizeof(wchar_t));
      }
    };
#endif

  template<>
    struct hash<float>
    : public std::unary_function<float, std::size_t>
    {
      std::size_t
      operator()(float fval) const
      {
	std::size_t result = 0;

	// 0 and -0 both hash to zero.
	if (fval != 0.0f)
	  result = Fnv_hash<>::hash(reinterpret_cast<const char*>(&fval),
				    sizeof(fval));
	return result;
      }
    };

  template<>
    struct hash<double>
    : public std::unary_function<double, std::size_t>
    {
      std::size_t
      operator()(double dval) const
      {
	std::size_t result = 0;

	// 0 and -0 both hash to zero.
	if (dval != 0.0)
	  result = Fnv_hash<>::hash(reinterpret_cast<const char*>(&dval),
				    sizeof(dval));
	return result;
      }
    };

  // For long double, careful with random padding bits (e.g., on x86,
  // 10 bytes -> 12 bytes) and resort to frexp.
  template<>
    struct hash<long double>
    : public std::unary_function<long double, std::size_t>
    {
      std::size_t
      operator()(long double ldval) const
      {
	std::size_t result = 0;

	int exponent;
	ldval = std::frexp(ldval, &exponent);
	ldval = ldval < 0.0l ? -(ldval + 0.5l) : ldval;

	const long double mult = std::numeric_limits<std::size_t>::max() + 1.0l;
	ldval *= mult;

	// Try to use all the bits of the mantissa (really necessary only
	// on 32-bit targets, at least for 80-bit floating point formats).
	const std::size_t hibits = (std::size_t)ldval;
	ldval = (ldval - (long double)hibits) * mult;

	const std::size_t coeff =
	  (std::numeric_limits<std::size_t>::max()
	   / std::numeric_limits<long double>::max_exponent);

	result = hibits + (std::size_t)ldval + coeff * exponent;

	return result;
      }
    };
}
}

#endif