what's the point of rpython?

[alex23]

On Jan 18, 9:55 am, "Brendan Miller" <catph... at catphive.net> wrote:
> > The *actual* goal as outlined by their official docs is to
> > implement Python in Python, at every level.
> Ok fair enough. In some ways I see that as more of a purely
> intellectual exercise than the practical endeavor that I assumed the
> project was originally.

Well, it opens up Python as a whole for experimentation & modification
by Python developers, which seems pretty practical to me :)

> Another question I was wondering about is whether they plan on
> maintaining good C bindings? Will existing bindings for third party
> libraries be able to work?

You really should run through the whole faq:

http://codespeak.net/pypy/dist/pypy/doc/faq.html#can-i-use-cpython-extension-modules

(Spoiler alert: the answer is no.)

> Also, are they going to do away with the GIL?

One FAQ entry before the above:

http://codespeak.net/pypy/dist/pypy/doc/faq.html#do-threads-work-what-are-the-modules-that-work

> The python devs seem to
> consider the GIL a non-issue, though they may change their mind in 3
> years when we all have 32 core desktops, until then getting rid of the
> GIL would make pypy pretty attractive in some quarters. I know the
> scons project was running into GIL issues.

It's not a case of the Python devs digging their heels in and not
giving the world what it desperately wants. Here's an article by Guido
talking about the last attempt to remove the GIL and the performance
issues that arose:

"I'd welcome a set of patches into Py3k *only if* the performance for
a single-threaded program (and for a multi-threaded but I/O-bound
program) *does not decrease*."

http://www.artima.com/weblogs/viewpost.jsp?thread=214235

> Finally, I'm pretty unclear on what versions of python that pypy is targeting.

I wonder where such a frequently asked question could be answered? ;)

http://codespeak.net/pypy/dist/pypy/doc/faq.html#which-python-version-2-x-does-pypy-implement