It seems like there's still a lot of discussion going on about the interface even when Vladimir is plodding on, so I thought I might offer another candidate that I haven't seen put forth just yet.
I personally do not mind wotking in such a mode. I am merely implemeting what we are seemingly settling on (as far as my interpretation goes) like 'convert' as a class, etc. to see how it works out in reality. And, therefore, my "plodding on" should not be an ideas' deterrent of any kind.
template<class Target, class Source> *unspecified-type* convert_to(const Source& value);
This would give us the flexibility to easily implement an interface that could be used like so:
int i = convert_to<int>("5").get(); // get "5" converted to int (throw on error)
unsigned u = convert_to<unsigned>("-1").get_or(0); // get "-1" converted to unsigned or else 0
int i = convert_to<int>("0xff").get_special(as_hex()); // get "0xff" converted to int using as_hex functor
My immediate concern is a lot of new vocabulary introduced. That can provide tons of useful stuff... that the majority of people might never use. Secondly, I am not sure what are the advantages of the alternative interface above. We seem to achieve all the above with the existing interface and only 1 (!) new keyword ("convert_to") in stad of 5 (convert_to, get, get_or, get_special, as_hex). // get "5" converted to int (throw on error) int i = convert_to<int>("5")(throw_t()); // get "-1" converted to unsigned or else 0 unsigned u = convert_to<unsigned>("-1", 0); // get "0xff" converted to int using as_hex functor int i = convert_to<int>("0xff") >> std::hex; With all due respect the interface immediately above looks (to me) more consistent and easier extendable. [snip] Still, I am keeping an open mind on that. If something else comes up, I may well flip onto your side (the current implementation already looks nothing as what I started with showing what a "flipper" I am). :-) V.