[Boost-users] [qi][lambda] Get wrong reaction of the qi::rule if I use lambda for the action

Hello, if I execute the following example, I get the following output "The bad one The good one a" but I only expected "The good one a". Why does it happens? Boost 1.47.0 was used. #include #include #include #include <iostream> int main() { using boost::spirit::qi::char_; using boost::spirit::qi::parse; char const *first = "{a}", *last = first + std::strlen(first); parse(first, last, '{' >> char_("a")[std::cout << "The good one " << boost::lambda::_1 << '\n'] | char_("b")[std::cout << "The bad one " << boost::lambda::_1 << '\n'] >> '}'); return 0; }