I have a PP interface such as the following: #define MACRO(x) \ typedef x type; \ typedef x::nested nested; struct D { struct nested {}; }; It is intended to be used as follows: struct foo { MACRO(D) }; Now the problem comes when x is a dependent type, because "typedef x::nested" needs a "typename" in there. I would like to additionally support the following syntax (or something like it): template<class DD> struct bar { MACRO(typename DD) }; The above doesn't work as is because "typedef typename DD type;" is ill-formed (although msvc eats it). Constraints are i/ the interface must be backwards compatible to avoid breaking existing clients, ii/ it should be done with PP only. No templates should be instantiated here, and iii/ it should be standard C++03. No PP variadics. Is this possible? I think not, but my PP-foo is weak. -- Eric Niebler BoostPro Computing http://www.boostpro.com