libcxx/test/std/utilities/meta/meta.unary/meta.unary.prop/is_const.pass.cpp

   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 // type_traits
  10
  11 // is_const
  12
  13 #include <type_traits>
  14 #include "test_macros.h"
  15
  16 template <class T>
  17 void test_is_const()
  18 {
  19     static_assert(!std::is_const<T>::value, "");
  20     static_assert( std::is_const<const T>::value, "");
  21     static_assert(!std::is_const<volatile T>::value, "");
  22     static_assert( std::is_const<const volatile T>::value, "");
  23 #if TEST_STD_VER > 14
  24     static_assert(!std::is_const_v<T>, "");
  25     static_assert( std::is_const_v<const T>, "");
  26     static_assert(!std::is_const_v<volatile T>, "");
  27     static_assert( std::is_const_v<const volatile T>, "");
  28 #endif
  29 }
  30
  31 struct A; // incomplete
  32
  33 int main(int, char**)
  34 {
  35     test_is_const<void>();
  36     test_is_const<int>();
  37     test_is_const<double>();
  38     test_is_const<int*>();
  39     test_is_const<const int*>();
  40     test_is_const<char[3]>();
  41     test_is_const<char[]>();
  42
  43     test_is_const<A>();
  44
  45     static_assert(!std::is_const<int&>::value, "");
  46     static_assert(!std::is_const<const int&>::value, "");
  47
  48   return 0;
  49 }