// { dg-do run { target c++11 } }

// Copyright (C) 2016-2017 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();
}
