A couple of days ago I started work on a library where I need a way to represent rational numbers and fixed point precision numbers at compile time, so I started creating a compile-time rational number type following the style of integral_c in boost::mpl. After completing most operations, I notices that in the mpl/math directory there were already the beginnings of rational_c and fixed_c types, however, they are far from complete (in rational_c there are just two static constants for numerator and denominator and a self typedef, with no specialized operations). Are these types still in development or are they abandoned? I'd like to continue my project using mpl::rational_c and mpl::fixed_c as I need to make them work with the mpl integral constants anyways. So is development on these templates halted, meaning I should just go ahead and finish my types, or are the types coming soon enough so I just should just hold off and wait for the cavalry to arrive?