libcxx/test/std/utilities/meta/meta.unary/meta.unary.prop/is_nothrow_assignable.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_nothrow_assignable
  12
  13 #include <type_traits>
  14 #include "test_macros.h"
  15
  16 template <class T, class U>
  17 void test_is_nothrow_assignable()
  18 {
  19     static_assert(( std::is_nothrow_assignable<T, U>::value), "");
  20 #if TEST_STD_VER > 14
  21     static_assert(( std::is_nothrow_assignable_v<T, U>), "");
  22 #endif
  23 }
  24
  25 template <class T, class U>
  26 void test_is_not_nothrow_assignable()
  27 {
  28     static_assert((!std::is_nothrow_assignable<T, U>::value), "");
  29 #if TEST_STD_VER > 14
  30     static_assert((!std::is_nothrow_assignable_v<T, U>), "");
  31 #endif
  32 }
  33
  34 struct A
  35 {
  36 };
  37
  38 struct B
  39 {
  40     void operator=(A);
  41 };
  42
  43 struct C
  44 {
  45     void operator=(C&);  // not const
  46 };
  47
  48 int main(int, char**)
  49 {
  50     test_is_nothrow_assignable<int&, int&> ();
  51     test_is_nothrow_assignable<int&, int> ();
  52 #if TEST_STD_VER >= 11
  53     test_is_nothrow_assignable<int&, double> ();
  54 #endif
  55
  56     test_is_not_nothrow_assignable<int, int&> ();
  57     test_is_not_nothrow_assignable<int, int> ();
  58     test_is_not_nothrow_assignable<B, A> ();
  59     test_is_not_nothrow_assignable<A, B> ();
  60     test_is_not_nothrow_assignable<C, C&> ();
  61
  62   return 0;
  63 }