libcxx/test/std/utilities/meta/meta.unary/meta.unary.comp/is_reference.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_reference
  12
  13 #include <type_traits>
  14 #include <cstddef>         // for std::nullptr_t
  15 #include "test_macros.h"
  16
  17 template <class T>
  18 void test_is_reference()
  19 {
  20     static_assert( std::is_reference<T>::value, "");
  21     static_assert( std::is_reference<const T>::value, "");
  22     static_assert( std::is_reference<volatile T>::value, "");
  23     static_assert( std::is_reference<const volatile T>::value, "");
  24 #if TEST_STD_VER > 14
  25     static_assert( std::is_reference_v<T>, "");
  26     static_assert( std::is_reference_v<const T>, "");
  27     static_assert( std::is_reference_v<volatile T>, "");
  28     static_assert( std::is_reference_v<const volatile T>, "");
  29 #endif
  30 }
  31
  32 template <class T>
  33 void test_is_not_reference()
  34 {
  35     static_assert(!std::is_reference<T>::value, "");
  36     static_assert(!std::is_reference<const T>::value, "");
  37     static_assert(!std::is_reference<volatile T>::value, "");
  38     static_assert(!std::is_reference<const volatile T>::value, "");
  39 #if TEST_STD_VER > 14
  40     static_assert(!std::is_reference_v<T>, "");
  41     static_assert(!std::is_reference_v<const T>, "");
  42     static_assert(!std::is_reference_v<volatile T>, "");
  43     static_assert(!std::is_reference_v<const volatile T>, "");
  44 #endif
  45 }
  46
  47 class incomplete_type;
  48
  49 class Empty
  50 {
  51 };
  52
  53 class NotEmpty
  54 {
  55     virtual ~NotEmpty();
  56 };
  57
  58 union Union {};
  59
  60 struct bit_zero
  61 {
  62     int :  0;
  63 };
  64
  65 class Abstract
  66 {
  67     virtual ~Abstract() = 0;
  68 };
  69
  70 enum Enum {zero, one};
  71
  72 typedef void (*FunctionPtr)();
  73
  74
  75 int main(int, char**)
  76 {
  77     test_is_reference<int&>();
  78     test_is_reference<int&&>();
  79     test_is_not_reference<std::nullptr_t>();
  80     test_is_not_reference<void>();
  81     test_is_not_reference<int>();
  82     test_is_not_reference<double>();
  83     test_is_not_reference<char[3]>();
  84     test_is_not_reference<char[]>();
  85     test_is_not_reference<void *>();
  86     test_is_not_reference<FunctionPtr>();
  87     test_is_not_reference<Union>();
  88     test_is_not_reference<incomplete_type>();
  89     test_is_not_reference<Empty>();
  90     test_is_not_reference<bit_zero>();
  91     test_is_not_reference<int*>();
  92     test_is_not_reference<const int*>();
  93     test_is_not_reference<Enum>();
  94     test_is_not_reference<NotEmpty>();
  95     test_is_not_reference<Abstract>();
  96     test_is_not_reference<int(int)>();
  97     test_is_not_reference<int Empty::*>();
  98     test_is_not_reference<void (Empty::*)(int)>();
  99
 100
 101   return 0;
 102 }