

PyPy support for Python 3 (pypy-dev) - kbd
http://mail.python.org/pipermail/pypy-dev/2011-September/008288.html

======
sho_hn
Warms my heart to read a solid confirmation that PyPy as a project is
committed to implementing Python 3 support. For some time now I've been
lamenting the dilemma that is having to choose between PyPy and CPython 3.x,
plus it's always left a bit of a bitter after-taste that any rise in the
popularity of PyPy would serve to prolong the transition pains as long as
there wasn't a clear and public plan toward Python 3 support.

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kbd
Additional discussion on reddit:
[http://www.reddit.com/r/Python/comments/kd38b/pypys_python_3...](http://www.reddit.com/r/Python/comments/kd38b/pypys_python_3_plan/)

~~~
sho_hn
There's discussion of the Python version supported by AppEngine in there ...
it's funny to think that once PyPy supports Python 3, and assuming the RPython
interpreter implementing that support will still be compatible with Python
2.x, you might actually be able to use Python 3 on AppEngine by running PyPy's
Python 3 interpreter against whatever Python 2.x AppEngine offers.

In fact, has anyone tried running PyPy's 2.7 interpreter on AppEngine's 2.5?

Not that I would expect such a setup to be production-ready, but just for the
fun of it ...

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amirhhz
What are the builtin and third-party libraries that people have had trouble
with when using PyPy (modulo having to configure an appication to use PyPy at
runtime instead of CPython)? For web-dev, scientific or otherwise?

In particular, are there any such problem cases where there is insufficient
documentation?

~~~
old-gregg
Cython is the biggest issue right now with PyPy: lots of 3rd party libraries
depend on it, lxml and pyzmq come to mind.

I can't wait for Cython support: in our tests PyPy delivers amazing RAM
savings, PyPy seems to have a particularly efficient list implementation
specialized for small strings: we're seeing x3 savings there, in addition to
20% speedup.

~~~
axiak
If Cython compiles to standard c modules, and pypy claims to support standard
c modules in its latest release, doesn't pypy now support Cython? (In the same
way that Cpython does?)

~~~
MostAwesomeDude
PyPy's support for the C API is highly limited and not something to be relied
upon for new code. IIRC the Cython plan is for Cython to grow the ability to
emit pure Python with ctypes.

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jevinskie
What is with the estimated costs? Are they looking for corporate sponsors?
I've never seen a FOSS project do such a thing when discussing future plans.

~~~
unshift
they don't expect the work to be done solely by volunteers, and are going to
ask for donations on their website. it's laid out in the first paragraphs:

    
    
         The task is huge and it's unlikely that it will be 
         completed shortly based only on volunteer work, so we 
         came up with the following proposal, which splits the 
         work into several steps and sub-steps, togheter with an 
         estimate of how much money is needed to complete each 
         one.

~~~
kbd
I really wish Google would support PyPy. It'd be such a small amount of money
for them to fund development. Given the PyPy team's demonstrable success and
Google's otherwise strong commitment to Python I can't understand why they
don't.

~~~
sho_hn
That Unladden Swallow seems to have died a quiet death in the end sure doesn't
support the idea that Google is easy to truely commit to such efforts, though.

~~~
bdr
My impression is that's because it was a failure technically, not because
Google didn't support its goals.

~~~
sho_hn
I thought the story was that the Unladden Swallow team had actually started
expanding into new directions after walking away from LLVM disappointed, but
the project then got cancelled from higher-up?

I guess my point, in keeping with the parent, is that you'd expect Google to
be interested in sustaining a team looking into performance improvements in an
important part of their runtime longer-term, but that didn't happen.

Edit: On an unrelated note, it's good fun to take a look at
<http://speed.pypy.org/> and consider how close the averaged 4.5x speedup of
PyPy trunk over CPython is to the original "make it five times faster" goal of
Unladden Swallow.

~~~
archangel_one
There's a retrospective here which addresses quite a lot of it:
[http://qinsb.blogspot.com/2011/03/unladen-swallow-
retrospect...](http://qinsb.blogspot.com/2011/03/unladen-swallow-
retrospective.html)

Partly it sounds like performance-critical code at Google tends to get written
in a lower level language instead, so Python performance isn't as critical,
even though they use it quite a bit.

Agree that it'd be great if they helped out the PyPy team though, since it's
showing such great promise and has some pretty impressive numbers already.

------
densh
Actual donation page:

<http://pypy.org/py3donate.html>

