I would like to thank you for that such a great explanation of the Template-based programming in that unary example. I think it's great you have uploaded that to the wiki4d, and it's definite will help a lot of people that come from other common languages background (like C, C# and Python) that don't support full templating, to understand that design pattern. And with that close tracking to the functional.d code, I thing but not sure that we've found some bugs. I will do some testing later today, and if I will see what I think to be wrong, I'll update.
and again, Thanks