Hi Goran,

First, why there isn't a way to register wstring type, even though I've registered wchar_t? I've managed to use it only after I've registered basic_string template with one template parameter. Seems inpractical...

There are a few choices here: 1) BOOST_TYPEOF_REGISTER_TYPE(wstring); 2) BOOST_TYPEOF_REGISTER_TYPE(wchar_t); BOOST_TYPEOF_REGISTER_TEMPLATE(std::basic_string, 1); 3) BOOST_TYPEOF_REGISTER_TYPE(wchar_t); BOOST_TYPEOF_REGISTER_TEMPLATE(std::basic_string, 3); BOOST_TYPEOF_REGISTER_TEMPLATE(std::char_traits, 1); BOOST_TYPEOF_REGISTER_TEMPLATE(std::allocator, 1); Pre-registration of STL types would be a very nice addition to the library. For now I am avoiding this, and trying to focus on the facility itself.

Second problem, no matter whether I've used wstring or basic_string for registration, I wasn't able to get a type of wstring::iterator expression!

This is much more complicated problem, and I am not sure it can be resolved... The problem is that you can't specialize (or overload) on a nested types. The Standard clearly says that this is a non-deducible context. So we can't do something like: template<class V, class T> encode_type<V, T::iterator>{}; // compiler error! This is VERY unfortunate, and I 've been trying to think of workarounds, but so far I only came up with one that is quite limited and ugly... So I decided to put this on hold. Regards, Arkadiy