I've been extensively using boost::tuple for a while and stumbled upon various tuple size limitation bound to the fact that the tuple implementation has hardcoded the maximum size of the tuple<> class and related function/meta-functions like tie for example or make_tuple. Is there anything in tuple design that prevent using Boost::Preprocessor to make it more customizable ? Is there an interest to such an update or is tuples more or less on the way to deprecation considering boost::fusion ?