Thank you. I will read the docs. It seems Boost::proto will do the derivation for me, while I still have to write the AST myself. This AST, isn't there already some boost implementation of it somewhere? After all, writing symbolic mathematical functions would seem to me something many users require. Well, that's proto works too. Given a grammar and a set of terminals, it'll give you compile-time access to the AST and to a large selection of operations on it.
Performance is first factor for the code I am writing, so I am trying to run as much as possible at compile-time, as a matter of principle. But I guess making a function object out of the AST will be cheap. I will now move the literals from the compile-time to the run-time world, and will get all numeric types then.
Should be more than enough IMHO -- Joel FALCOU Research Engineer @ Institut d'Electronique Fondamentale Université PARIS SUD XI France