如何使用boost :: iostreams管道进入std :: cout

Question

我是新手,boost::iostreams所以这可能是微不足道的:

假设 namespace io = boost::iostreams;

这很有效

io::filtering_ostream out(std::cout);
out << "some\nstring\n";

这很有效

std::string result;
io::filtering_ostream out(io::counter() | io::back_inserter(result));
out << "some\nstring\n";

但这不编译

io::filtering_ostream out(io::counter() | std::cout);
out << "some\nstring\n";

你怎么管std::cout？

Answer 1

std::cout用boost :: ref包装为我工作:

io::filtering_ostream out(DummyOutputFilter() | boost::ref(std::cout));

有关详细信息,请参阅pipable 文档中的note_1.