[Cython] Bringing Cython and PyPy closer together

[Stefan Behnel]

Hi,

following up on the thread on the PyPy mailing list where this topic was
started, I've started a CEP in our Wiki in order to focus the different
ideas and opinions.

http://wiki.cython.org/enhancements/pypy

The current state of the discussion seems to be that PyPy provides ways to
talk to C code, but nothing as complete as CPython's C-API in the sense
that it allows efficient two-way communication between C code and Python
objects. Thus, we need to either improve this or look for alternatives.

Please add to the CEP as you see fit.

Stefan