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rs6000.c (rs6000_option_override_internal): Fix two typographic errors in the handlin...
[thirdparty/gcc.git] / libstdc++-v3 / testsuite / 20_util / variant / hash.cc
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1// { dg-options "-std=gnu++17" }
2
cbe34bb5 3// Copyright (C) 2016-2017 Free Software Foundation, Inc.
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4//
5// This file is part of the GNU ISO C++ Library. This library is free
6// software; you can redistribute it and/or modify it under the
7// terms of the GNU General Public License as published by the
8// Free Software Foundation; either version 3, or (at your option)
9// any later version.
10
11// This library is distributed in the hope that it will be useful,
12// but WITHOUT ANY WARRANTY; without even the implied warranty of
13// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14// GNU General Public License for more details.
15
c7cbb4da 16// You should have received a copy of the GNU General Public License along
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17// with this library; see the file COPYING3. If not see
18// <http://www.gnu.org/licenses/>.
19
20#include <variant>
21#include <testsuite_hooks.h>
22
23class S{}; // No hash specialization
24
25template<class T>
26auto f(int) -> decltype(std::hash<std::variant<T>>(), std::true_type());
27
28template<class T>
29auto f(...) -> decltype(std::false_type());
30
31static_assert(!decltype(f<S>(0))::value, "");
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32static_assert(!decltype(f<std::variant<S>>(0))::value, "");
33static_assert(!decltype(f<std::variant<S, S>>(0))::value, "");
34static_assert(decltype(f<std::variant<int>>(0))::value, "");
35static_assert(decltype(f<std::variant<int, int>>(0))::value, "");
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36static_assert(!std::is_callable<
37 std::hash<std::variant<S>>&(std::variant<S> const&)>::value, "");
38static_assert(!std::is_callable<
39 std::hash<std::variant<S, int>>&
40 (std::variant<S, int> const&)>::value, "");
41static_assert(std::is_callable<
42 std::hash<std::variant<int>>&
43 (std::variant<int> const&)>::value, "");
44static_assert(std::is_callable<
45 std::hash<std::variant<int, int>>&
46 (std::variant<int, int> const&)>::value, "");
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47
48int main()
49{
50 int x = 42;
51 std::variant<int> x2 = 42;
52 VERIFY(std::hash<int>()(x) == std::hash<std::variant<int>>()(x2));
53}