I am writing template math functions. Some can take integral types (only) Some can take real (both built-in floating-point - float, double.. AND User Defined real types) And some can take either integral OR real. Real : Floating-point types Integer : Integral types Arithmetic : Either Integral OR Floating-point types Arithmetic is a bit long - other ideas? So to write a function something like template <class RealType> RealType students_t(ArithmeticType degrees_of_freedom, RealType t) { ... } Using just T is not an option because there are three (at least) possibles. What names should I use for the types? RealType, real_type, RealT, or RT, or ??? IntType, int_type, IntT, IT, or ??? ArithmeticType, arithmetic_type, ArithType, arith_type, AT ??? Suggestions for names please. Rationales? Prior art? Precedents? Standards? Thanks Paul --- Paul A Bristow Prizet Farmhouse, Kendal, Cumbria UK LA8 8AB +44 1539561830 & SMS, Mobile +44 7714 330204 & SMS pbristow@hetp.u-net.com