The current tuple output mechanism wants me to say cout << formatting_manipulator << tuple; The expression (cout << formatting_manipulator) return an "embossed" cout, but currently it returns just cout with internal settings modified. The call must change things allocated within cout, like the standard manipulators do; although it is supported by the standard output, I find this approach so CFront-ish. How about using the syntax (cout << format_specification (tuple)) instead? Or even (cout << tuple / format_specification)? Chris