[pypy-dev] Question on the future of RPython

Paolo Giarrusso p.giarrusso at gmail.com
Thu Sep 2 16:10:07 CEST 2010

On Thu, Sep 2, 2010 at 10:18, Saravanan Shanmugham <sarvi at yahoo.com> wrote:
> I have researched these projects quite extensively.
> Quite similar beasts as far as I can tell.
> Cython/Pyrex used to write python extensions. They use statically typed variants
> of Python which gets compiled into C which can then be compiled.
> Shedskin is slightly more general purpose Restricted Python to C++ compiler.
> PyPy as I understand can convert RPython into C code
> Am I missing something here?

Maybe you have done extensive research, but the above is not enough
for the conclusion, which might still be valid.
There could be some cool way to reuse each other's code, and that
would be cool given the available manpower.

The question is:
=> Do different goals cause _incompatible_ design/implementation choices?
Currently, static typing versus global type inference seems to be
already a fundamental difference. Modular type inference, if
polymorphic (and I guess it has to be), would require using boxed or
tagged integers more often, as far as I can see.

RPython is intended to be compiled to various environments, with
different variations (choose GC/stackful or stackless/heaps of other
choices), and its programmers are somewhat OK with its limitations; it
has type inference, with its set of tradeoffs. This for instance
prevents reusing shedskin, and probably even prevents reusing any of
its code.

Cython/Shedskin are intended to be used by more people and to be simpler.

==> Would making RPython usable for people harm its usability for PyPy?

I see no trivial answer to the above questions which allows merging,
but I don't develop any of them.
However, a discussion of this could probably end in a PyPy FAQ.

Best regards
Paolo Giarrusso - Ph.D. Student

More information about the Pypy-dev mailing list