xref: /llvm-project/libc/src/__support/CPP/type_traits/is_signed.h (revision 5ff3ff33ff930e4ec49da7910612d8a41eb068cb)
1 //===-- is_signed type_traits -----------------------------------*- C++ -*-===//
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 #ifndef LLVM_LIBC_SRC___SUPPORT_CPP_TYPE_TRAITS_IS_SIGNED_H
9 #define LLVM_LIBC_SRC___SUPPORT_CPP_TYPE_TRAITS_IS_SIGNED_H
10 
11 #include "src/__support/CPP/type_traits/bool_constant.h"
12 #include "src/__support/CPP/type_traits/is_arithmetic.h"
13 #include "src/__support/macros/attributes.h"
14 #include "src/__support/macros/config.h"
15 
16 namespace LIBC_NAMESPACE_DECL {
17 namespace cpp {
18 
19 // is_signed
20 template <typename T>
21 struct is_signed : bool_constant<(is_arithmetic_v<T> && (T(-1) < T(0)))> {
22   LIBC_INLINE constexpr operator bool() const { return is_signed::value; }
23   LIBC_INLINE constexpr bool operator()() const { return is_signed::value; }
24 };
25 template <typename T>
26 LIBC_INLINE_VAR constexpr bool is_signed_v = is_signed<T>::value;
27 
28 } // namespace cpp
29 } // namespace LIBC_NAMESPACE_DECL
30 
31 #endif // LLVM_LIBC_SRC___SUPPORT_CPP_TYPE_TRAITS_IS_SIGNED_H
32