A while back it was mentioned that boost::mpl::rational_c and boost::mpl::fixed_c needed redesigning. Before I attempt to tackle this task anymore than I already have, I should have some questions answered. 1. For those compilers for which BOOST_NO_LIMITS is defined, I've learned that there is no way to include a floating-point number in an integral constant expression. Does this mean that no matter how I define fixed_c::value, I cannot pass fixed_c as a template argument to a metafunction that ordinarily takes integral_c as input? Do I have to duplicate the functionality as a result? If so, what should be the naming convention for these new metafunctions? 2. Should I define fixed_c in terms of rational_c, to reduce the amount of functionality I may need to duplicate? Something like this: template <typename IntType, IntType N, IntType PowerOf10> struct fixed_c { typedef rational_c<IntType,...,...> type; }; 3. Eventually the compile-time rational-number representation will need to be converted to a runtime floating-point value. Should I define this conversion function within rational_c (which means an additional template parameter, with either function or class scope, defining the return value type), within a wrapper struct, or somewhere else? And how? 4. I only have to deal with rational numbers, right? I don't have to worry about accurately representing a transcendental number or a complex-number expression? TIA! Cromwell Enage __________________________________ Do you Yahoo!? Yahoo! Domains � Claim yours for only $14.70/year http://smallbusiness.promotions.yahoo.com/offer