This code: std::string s("blablabla"); std::string::iterator start = s.begin(); std::string::iterator finish = s.end();         bool result = phrase_parse(start, finish, +(!char_(':')), space); It's just a simple parser that match string which doesn't have ':' character in it right ? But when I run it, function phrase_parse is hang, it never return anything. I'm using boost 1.44 with VC 2008