Expression template in D struct

[The Anh Tran]

Hi,

I'm converting my pet project from C++ to D. It is an aimbot game cheat.
One of my C++ struct is Vector3. It is a wrapper from D3DXVECTOR3.
I would like to use expression template to calculate where to point the 
gun. In C++, it is provided by boost::proto or boost::ublas.

My naive implementation (in fact, "copy&paste" from c++ book "thinking 
in c++") refused to compile.
I've searched dsource.org; the nearest match is Don's BLADE library.

Is there any tutorial, or simpler way to do expression in D; without 
building AST as in BLADE?

Thanks.