OK, clearly it's not a field I'm familiar with - for that reason I'd prefer not to be the one to write a backend for that - or at least I would need some considerable help - but I see no real obstacles to supporting such a type providing you don't want the transcendental functions. If someone were willing to be the guinea pig, then it might make a good test case for seeing how easy it is for someone other than me to extend the library?
This is something I would be willing to contribute but probably not until after the formal review.
Nod, thanks. Also just realized that while a simple adapter backend: template <class BigInteger> class exact_float; Would be more or less trivial as far as the arithmetic goes, other stuff like string conversion would be *much* more complex, exactly which conversions and/or string formatting should be supported would require some careful thought. Regards, John.