[Cython] [cython-users] GSoC 2012

[Stefan Behnel]

mark florisson, 11.03.2012 07:44:
> - better type inference, that would be enabled by default and again
> handle thing like reassignments of variables and fallbacks to the
> default object type. With entry caching Cython could build a database
> of types ((extension) classes, functions, variables) used in the
> modules and functions that are compiled (also def functions), and
> infer the types used and specialize on those. Maybe a switch should be
> added to cython to handle circular dependencies, or maybe with the
> distutils preprocessing it can run all the type inference first and
> keep track of unresolved entries, and try to fill those in after
> building the database. For bonus points the user can be allowed to
> write plugins to aid the process.

That would be my favourite. We definitely need control flow driven type
inference, local type specialisation, variable renaming, etc. Maybe even
whole program (or at least module) analysis, like ShedSkin and PyPy do for
their restricted Python dialects. Any serious step towards that goal would
be a good outcome of a GSoC.

There's also better support for PyPy through its cpyext C-API layer, but
that currently involves much more work on PyPy than on Cython, including a
lot of performance optimisation on their side. And there doesn't seem to be
much interest in the PyPy project for doing this.

Stefan