_typetraits.h

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// -*- C++ -*-
 
#ifndef _RWSTD_TYPETRAITS_H_INCLUDED
#define _RWSTD_TYPETRAITS_H_INCLUDED
 
 
#include <rw/_defs.h>
 
 
_RWSTD_NAMESPACE (__rw) { 
 
template <class T, T v>
struct __rw_integral_constant
{
    static constexpr T value = v;
    using value_type = T;
    using type = integral_constant;
 
    constexpr operator value_type() const noexcept { return value; }
    constexpr value_type operator()() const noexcept { return value; }
};
 
using __rw_true_type = __rw_integral_constant<bool, true>;
using __rw_false_type = __rw_integral_constant<bool, false>;
 
template <class _TypeT>
struct __rw_is_const
{
    typedef _TypeT _C_type;
    enum { _C_val = 0 };
};
 
template <class _TypeT>
struct __rw_is_const<const _TypeT>
{
    typedef _TypeT _C_type;
    enum { _C_val = 1 };
};
 
template <class _TypeT>
struct __rw_is_volatile
{
    typedef _TypeT _C_type;
    enum { _C_val = 0 };
};
 
template <class _TypeT>
struct __rw_is_volatile<volatile _TypeT>
{
    typedef _TypeT _C_type;
    enum { _C_val = 1 };
};
 
 
template <class _TypeT>
struct __rw_is_cv_qualified
{
    typedef _TypeT _C_type;
    enum { _C_val = 0 };
};
 
template <class _TypeT>
struct __rw_is_cv_qualified<const _TypeT>
{
    typedef _TypeT _C_type;
    enum { _C_val = 1 };
};
 
template <class _TypeT>
struct __rw_is_cv_qualified<volatile _TypeT>
{
    typedef _TypeT _C_type;
    enum { _C_val = 1 };
};
 
template <class _TypeT>
struct __rw_is_cv_qualified<const volatile _TypeT>
{
    typedef _TypeT _C_type;
    enum { _C_val = 1 };
};
 
 
template <class _TypeT>
struct __rw_is_pointer
{
    typedef _TypeT _C_type;
    enum { _C_val = 0 };
};
 
template <class _TypeT>
struct __rw_is_pointer<_TypeT*>
{
    typedef _TypeT _C_type;
    enum { _C_val = 1 };
};
 
 
template <class _TypeT>
struct __rw_is_reference
{
    typedef _TypeT _C_type;
    enum { _C_val = 0 };
};
 
template <class _TypeT>
struct __rw_is_reference<_TypeT&>
{
    typedef _TypeT _C_type;
    enum { _C_val = 1 };
};
 
template <class _TypeT>
struct __rw_is_reference<_TypeT&&>
{
    typedef _TypeT _C_type;
    enum { _C_val = 1 };
};
 
template <class _TypeT>
struct __rw_is_fundamental
{
    enum { _C_val = __rw_is_pointer<_TypeT>::_C_val };
};
 
_RWSTD_SPECIALIZED_CLASS
struct __rw_is_fundamental<unsigned char> { enum { _C_val = 1 }; };
 
_RWSTD_SPECIALIZED_CLASS
struct __rw_is_fundamental<signed char> { enum { _C_val = 1 }; };
 
_RWSTD_SPECIALIZED_CLASS
struct __rw_is_fundamental<char> { enum { _C_val = 1 }; };
 
_RWSTD_SPECIALIZED_CLASS
struct __rw_is_fundamental<unsigned short> { enum { _C_val = 1 }; };
 
_RWSTD_SPECIALIZED_CLASS
struct __rw_is_fundamental<signed short> { enum { _C_val = 1 }; };
 
_RWSTD_SPECIALIZED_CLASS
struct __rw_is_fundamental<unsigned int> { enum { _C_val = 1 }; };
 
_RWSTD_SPECIALIZED_CLASS
struct __rw_is_fundamental<signed int> { enum { _C_val = 1 }; };
 
_RWSTD_SPECIALIZED_CLASS
struct __rw_is_fundamental<unsigned long> { enum { _C_val = 1 }; };
 
_RWSTD_SPECIALIZED_CLASS
struct __rw_is_fundamental<signed long> { enum { _C_val = 1 }; };
 
#ifdef _RWSTD_LONG_LONG
 
_RWSTD_SPECIALIZED_CLASS
struct __rw_is_fundamental<unsigned _RWSTD_LONG_LONG> { enum { _C_val = 1 }; };
 
_RWSTD_SPECIALIZED_CLASS
struct __rw_is_fundamental<signed _RWSTD_LONG_LONG> { enum { _C_val = 1 }; };
 
#endif   // _RWSTD_LONG_LONG
 
_RWSTD_SPECIALIZED_CLASS
struct __rw_is_fundamental<float> { enum { _C_val = 1 }; };
 
_RWSTD_SPECIALIZED_CLASS
struct __rw_is_fundamental<double> { enum { _C_val = 1 }; };
 
#ifndef _RWSTD_NO_LONG_DOUBLE
 
_RWSTD_SPECIALIZED_CLASS
struct __rw_is_fundamental<long double> { enum { _C_val = 1 }; };
 
#endif   // _RWSTD_NO_LONG_DOUBLE
 
#ifndef _RWSTD_NO_BOOL
 
_RWSTD_SPECIALIZED_CLASS
struct __rw_is_fundamental<bool> { enum { _C_val = 1 }; };
 
#endif   // _RWSTD_NO_BOOL
 
#ifndef _RWSTD_NO_NATIVE_WCHAR_T
 
_RWSTD_SPECIALIZED_CLASS
struct __rw_is_fundamental<wchar_t> { enum { _C_val = 1 }; };
 
#endif   // _RWSTD_NO_NATIVE_WCHAR_T
 
_RWSTD_SPECIALIZED_CLASS
struct __rw_is_fundamental<void> { enum { _C_val = 1 }; };
 
 
template <class _TypeT>
struct __rw_is_enum
{
    struct _C_no { };
    struct _C_yes { int _C_dummy [2]; };
 
    struct _C_indirect {
        // prevent classes with user-defined conversions from matching
 
        // use double to prevent float->int gcc conversion warnings
        _C_indirect (double);
    };
 
    // nested struct gets rid of bogus gcc errors
    struct _C_nest {
        // supply first argument to prevent HP aCC warnings
        static _C_no _C_is (int, ...);
        static _C_yes _C_is (int, _C_indirect);
 
        static _TypeT _C_make_T ();
    };
 
#if !defined (__HP_aCC) || __HP_aCC > 33000
 
    enum {
        _C_val =       sizeof (_C_yes)
                    == sizeof (_C_nest::_C_is (0, _C_nest::_C_make_T ()))
                 && !__rw_is_fundamental<_TypeT>::_C_val
    };
 
#else
 
    // prevent references from causing an error
    typedef typename __rw_is_reference<_TypeT>::_C_type _C_type;
 
    // working around an HP aCC bug (see PR #25347)
    // NOTE: this fails for classes due to another bug (PR #25384)
    static const bool
    _C_val =    sizeof (_C_yes) == sizeof (_C_nest::_C_is (0, _C_type ()))
             && !__rw_is_fundamental<_TypeT>::_C_val;
 
#endif   // __HP_aCC > 33000
 
};
 
 
#if defined (__HP_aCC) && __HP_aCC <= 33000
 
template <class _TypeT>
const bool __rw_is_enum<_TypeT>::_C_val;
 
#endif   // __HP_aCC <= 33000
 
 
_RWSTD_SPECIALIZED_CLASS
struct __rw_is_enum<void>
{
    enum { _C_val = 0 };
};
 
 
template <class _TypeT>
struct __rw_type_traits
{
    typedef typename __rw_is_const<_TypeT>::_C_type     _C_non_const_type;
    typedef typename __rw_is_volatile<_TypeT>::_C_type  _C_non_volatile_type;
    typedef typename __rw_is_pointer<_TypeT>::_C_type   _C_non_pointer_type;
    typedef typename __rw_is_reference<_TypeT>::_C_type _C_non_reference_type;
 
    typedef typename __rw_is_cv_qualified<_TypeT>::_C_type
    _C_non_cv_qualified_type;
 
    enum {
        _C_is_const        = __rw_is_const<_TypeT>::_C_val,
        _C_is_volatile     = __rw_is_volatile<_TypeT>::_C_val,
        _C_is_cv_qualified = __rw_is_cv_qualified<_TypeT>::_C_val,
        _C_is_pointer      = __rw_is_pointer<_TypeT>::_C_val,
        _C_is_reference    = __rw_is_reference<_TypeT>::_C_val,
        _C_is_fundamental  = __rw_is_fundamental<_TypeT>::_C_val,
        _C_is_enum         = __rw_is_enum<_TypeT>::_C_val,
        _C_is_class        =    !_C_is_pointer
                             && !_C_is_reference
                             && !_C_is_fundamental
                             && !_C_is_enum
    };
};
 
 
}   // namespace __rw
 
 
#endif   // _RWSTD_TYPETRAITS_H_INCLUDED