libcxx/test/std/utilities/meta/meta.rel/is_same.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_same
  12
  13 #include <type_traits>
  14
  15 #include "test_macros.h"
  16
  17 template <class T, class U>
  18 void test_is_same()
  19 {
  20     static_assert(( std::is_same<T, U>::value), "");
  21     static_assert((!std::is_same<const T, U>::value), "");
  22     static_assert((!std::is_same<T, const U>::value), "");
  23     static_assert(( std::is_same<const T, const U>::value), "");
  24 #if TEST_STD_VER > 14
  25     static_assert(( std::is_same_v<T, U>), "");
  26     static_assert((!std::is_same_v<const T, U>), "");
  27     static_assert((!std::is_same_v<T, const U>), "");
  28     static_assert(( std::is_same_v<const T, const U>), "");
  29 #endif
  30 }
  31
  32 template <class T, class U>
  33 void test_is_same_ref()
  34 {
  35     static_assert((std::is_same<T, U>::value), "");
  36     static_assert((std::is_same<const T, U>::value), "");
  37     static_assert((std::is_same<T, const U>::value), "");
  38     static_assert((std::is_same<const T, const U>::value), "");
  39 #if TEST_STD_VER > 14
  40     static_assert((std::is_same_v<T, U>), "");
  41     static_assert((std::is_same_v<const T, U>), "");
  42     static_assert((std::is_same_v<T, const U>), "");
  43     static_assert((std::is_same_v<const T, const U>), "");
  44 #endif
  45 }
  46
  47 template <class T, class U>
  48 void test_is_not_same()
  49 {
  50     static_assert((!std::is_same<T, U>::value), "");
  51 }
  52
  53 template <class T>
  54 struct OverloadTest
  55 {
  56     void fn(std::is_same<T, int>) { }
  57     void fn(std::false_type) { }
  58     void x() { fn(std::false_type()); }
  59 };
  60
  61 class Class
  62 {
  63 public:
  64     ~Class();
  65 };
  66
  67 int main(int, char**)
  68 {
  69     test_is_same<int, int>();
  70     test_is_same<void, void>();
  71     test_is_same<Class, Class>();
  72     test_is_same<int*, int*>();
  73     test_is_same_ref<int&, int&>();
  74
  75     test_is_not_same<int, void>();
  76     test_is_not_same<void, Class>();
  77     test_is_not_same<Class, int*>();
  78     test_is_not_same<int*, int&>();
  79     test_is_not_same<int&, int>();
  80
  81     OverloadTest<char> t;
  82     (void)t;
  83
  84   return 0;
  85 }