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// { dg-do run { target c++11 } }
// Copyright (C) 2016 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::ostream& operator<<(std::ostream&, const X&) = delete;
struct Y {};
std::ostream& operator<<(std::ostream& os, const Y&) {return os;}
std::ostream& operator<<(std::ostream&& os, const Y&) {return os;}
struct Z{};
template <class T>
auto f(T&&) -> decltype(void(std::declval<std::ostream&>()
<< std::declval<T&&>()),
std::true_type());
std::false_type f(...);
template <class T>
auto g(T&&) -> decltype(void(std::declval<std::ostream&&>()
<< std::declval<T&&>()),
std::true_type());
std::false_type g(...);
void test01()
{
Y y;
std::ostringstream os;
os << y;
os << Y();
std::ostringstream() << y;
std::ostringstream() << Y();
static_assert(!std::__is_insertable<std::ostream&, X&>::value, "");
static_assert(!std::__is_insertable<std::ostream&&, X&>::value, "");
static_assert(!std::__is_insertable<std::ostream&, X&&>::value, "");
static_assert(!std::__is_insertable<std::ostream&&, X&&>::value, "");
static_assert(std::__is_insertable<std::ostream&, Y&>::value, "");
static_assert(std::__is_insertable<std::ostream&&, Y&&>::value, "");
static_assert(std::__is_insertable<std::ostream&, Y&>::value, "");
static_assert(std::__is_insertable<std::ostream&&, Y&&>::value, "");
static_assert(!std::__is_insertable<std::ostream&, Z&>::value, "");
static_assert(!std::__is_insertable<std::ostream&&, Z&>::value, "");
static_assert(!std::__is_insertable<std::ostream&, Z&&>::value, "");
static_assert(!std::__is_insertable<std::ostream&&, 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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