"Taro" <taroso@gmail.com> wrote in message news:fefcdfb70801272201y10d57ebdo39d559ca5bc6e8a2@mail.gmail.com... | Theoretical Performance Differences: Since a typedef is purely | syntactic sugar, and all tranformational work would be done at | compilation, I think this is a key issue which, unfortunately, I believe, works against your proposal. If the alternative constructor is a builtin C function, then yes, the transformation could be done at compile time. But I think this much more difficult for one written in Python. As far as I know, the byte-code interpreter is not normally running during compilation. From __future__ imports work precisely because they are not really imports. But alternate constructor imports would have to be. I don't know enough, though, to know if this could be made to work. tjr