[boost] Tuples: how to get rid off the open/closing characters??

Hello, looking into the code, the documentation, and the proposed standard I can't find a way to output a boost::tuple to a stream with no opening and closing characters??? tuples::tuple_open requires a character, and thus one has to use some opening character, and equally some closing character???? (I can't believe this: Everybody knows that adding strings is much easier than erasing them.) Oliver