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// { dg-do run { target c++11 } }
// Copyright (C) 2016-2018 Free Software Foundation, Inc.
//
// This file is part of the GNU ISO C++ Library. This library is free
// software; you can redistribute it and/or modify it under the
// terms of the GNU General Public License as published by the
// Free Software Foundation; either version 3, or (at your option)
// any later version.
// This library is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU General Public License for more details.
// You should have received a copy of the GNU General Public License along
// with this library; see the file COPYING3. If not see
// <http://www.gnu.org/licenses/>.
// 27.6.2.5.3 basic_ostream manipulator inserters
#include <sstream>
struct X {};
std::istream& operator>>(std::istream&, X&) = delete;
struct Y {};
std::istream& operator>>(std::istream& is, Y&) {return is;}
std::istream& operator>>(std::istream& is, Y&&) {return is;}
struct Z{};
template <class T>
auto f(T&&) -> decltype(void(std::declval<std::istream&>()
>> std::declval<T&&>()),
std::true_type());
std::false_type f(...);
template <class T>
auto g(T&&) -> decltype(void(std::declval<std::istream&&>()
>> std::declval<T&&>()),
std::true_type());
std::false_type g(...);
void test01()
{
Y y;
std::istringstream is;
is >> y;
is >> Y();
std::istringstream() >> y;
std::istringstream() >> Y();
static_assert(!std::__is_extractable<std::istream&, X&>::value, "");
static_assert(!std::__is_extractable<std::istream&&, X&>::value, "");
static_assert(!std::__is_extractable<std::istream&, X&&>::value, "");
static_assert(!std::__is_extractable<std::istream&&, X&&>::value, "");
static_assert(std::__is_extractable<std::istream&, Y&>::value, "");
static_assert(std::__is_extractable<std::istream&&, Y&>::value, "");
static_assert(std::__is_extractable<std::istream&, Y&&>::value, "");
static_assert(std::__is_extractable<std::istream&&, Y&&>::value, "");
static_assert(!std::__is_extractable<std::istream&, Z&>::value, "");
static_assert(!std::__is_extractable<std::istream&&, Z&>::value, "");
static_assert(!std::__is_extractable<std::istream&, Z&&>::value, "");
static_assert(!std::__is_extractable<std::istream&&, Z&&>::value, "");
static_assert(std::is_same<decltype(f(std::declval<X&>())),
std::false_type>::value, "");
static_assert(std::is_same<decltype(f(std::declval<X&&>())),
std::false_type>::value, "");
static_assert(std::is_same<decltype(f(std::declval<Y&>())),
std::true_type>::value, "");
static_assert(std::is_same<decltype(f(std::declval<Y&&>())),
std::true_type>::value, "");
static_assert(std::is_same<decltype(f(std::declval<Z&>())),
std::false_type>::value, "");
static_assert(std::is_same<decltype(f(std::declval<Z&&>())),
std::false_type>::value, "");
static_assert(std::is_same<decltype(g(std::declval<X&>())),
std::false_type>::value, "");
static_assert(std::is_same<decltype(g(std::declval<X&&>())),
std::false_type>::value, "");
static_assert(std::is_same<decltype(g(std::declval<Y&>())),
std::true_type>::value, "");
static_assert(std::is_same<decltype(g(std::declval<Y&&>())),
std::true_type>::value, "");
static_assert(std::is_same<decltype(g(std::declval<Z&>())),
std::false_type>::value, "");
static_assert(std::is_same<decltype(g(std::declval<Z&&>())),
std::false_type>::value, "");
}
int main()
{
test01();
}
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