C++程序  |  33行  |  857 B

//===----------------------------------------------------------------------===//
//
//                     The LLVM Compiler Infrastructure
//
// This file is dual licensed under the MIT and the University of Illinois Open
// Source Licenses. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//

// UNSUPPORTED: c++98, c++03
//  Because we don't have a functioning decltype in C++03

// <memory>

// unique_ptr

// template<class CharT, class Traits, class Y, class D>
//   basic_ostream<CharT, Traits>&
//   operator<<(basic_ostream<CharT, Traits>& os, const unique_ptr<Y, D>& p);

#include <memory>
#include <sstream>
#include <cassert>

int main()
{
    std::unique_ptr<int> p(new int(3));
    std::ostringstream os;
    assert(os.str().empty());
    os << p;
    assert(!os.str().empty());
}