It would be nice if we could represent all compile-time algebraic operations in Boost.Units using MPL arithmetic. At present, MPL supports negate, adds, subtracts, times, divides. Boost.Units additionally would require : 1) unary_plus - the compile-time equivalent of operator+(T) 2) unary_minus - the compile-time equivalent of operator-(T); this is identical to current mpl::negate, but it would be nice to have it for notational consistency with unary_plus 3) power<T,U> (or pow<T,U>) - the compile-time equivalent of pow(T,U) 4) root<T,U> - the compile-time equivalent of pow(T,1/U); can be implemented with power<T,U>, but this is a nicer syntax to eliminate its remaining compile-time algebra operators. Any thoughts on whether this would be a worthwhile addition to MPL? Matthias