1 //===----------------------------------------------------------------------===// 2 // 3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. 4 // See https://llvm.org/LICENSE.txt for license information. 5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception 6 // 7 //===----------------------------------------------------------------------===// 8 9 #ifndef _LIBCPP___TYPE_TRAITS_IS_UNSIGNED_H 10 #define _LIBCPP___TYPE_TRAITS_IS_UNSIGNED_H 11 12 #include <__config> 13 #include <__type_traits/integral_constant.h> 14 #include <__type_traits/is_arithmetic.h> 15 #include <__type_traits/is_integral.h> 16 17 #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER) 18 # pragma GCC system_header 19 #endif 20 21 _LIBCPP_BEGIN_NAMESPACE_STD 22 23 // Before AppleClang 14, __is_unsigned returned true for enums with signed underlying type. 24 #if __has_builtin(__is_unsigned) && !(defined(_LIBCPP_APPLE_CLANG_VER) && _LIBCPP_APPLE_CLANG_VER < 1400) 25 26 template<class _Tp> 27 struct _LIBCPP_TEMPLATE_VIS is_unsigned : _BoolConstant<__is_unsigned(_Tp)> { }; 28 29 #if _LIBCPP_STD_VER > 14 30 template <class _Tp> 31 inline constexpr bool is_unsigned_v = __is_unsigned(_Tp); 32 #endif 33 34 #else // __has_builtin(__is_unsigned) 35 36 template <class _Tp, bool = is_integral<_Tp>::value> 37 struct __libcpp_is_unsigned_impl : public _BoolConstant<(_Tp(0) < _Tp(-1))> {}; 38 39 template <class _Tp> 40 struct __libcpp_is_unsigned_impl<_Tp, false> : public false_type {}; // floating point 41 42 template <class _Tp, bool = is_arithmetic<_Tp>::value> 43 struct __libcpp_is_unsigned : public __libcpp_is_unsigned_impl<_Tp> {}; 44 45 template <class _Tp> struct __libcpp_is_unsigned<_Tp, false> : public false_type {}; 46 47 template <class _Tp> struct _LIBCPP_TEMPLATE_VIS is_unsigned : public __libcpp_is_unsigned<_Tp> {}; 48 49 #if _LIBCPP_STD_VER > 14 50 template <class _Tp> 51 inline constexpr bool is_unsigned_v = is_unsigned<_Tp>::value; 52 #endif 53 54 #endif // __has_builtin(__is_unsigned) 55 56 _LIBCPP_END_NAMESPACE_STD 57 58 #endif // _LIBCPP___TYPE_TRAITS_IS_UNSIGNED_H 59