[Python-Dev] LZMA compression support in 3.3

[Antoine Pitrou]

On Sun, 28 Aug 2011 01:36:50 +1000
Nick Coghlan <ncoghlan at gmail.com> wrote:
> On Sun, Aug 28, 2011 at 1:15 AM, "Martin v. Löwis" <martin at v.loewis.de> wrote:
> > This is exactly what I worry about. I think adding file I/O to bz2 was a
> > mistake, as this doesn't integrate with Python's IO library (it used
> > to, but now after dropping stdio, they were incompatible. Indeed, for
> > Python 3.2, BZ2File has been removed from the C module, and lifted to
> > Python.
> >
> > IOW, the _lzma C module must not do any I/O, neither directly nor
> > indirectly (through liblzma). The approach of gzip.py (doing IO
> > and file formats in pure Python) is exactly right.
> 
> PEP 399 also comes into play - we need a pure Python version for PyPy
> et al (or a plausible story for why an exception should be granted).

The plausible story being that we basically wrap an existing library?
I don't think PyPy et al have pure Python versions of the zlib or
OpenSSL, do they?

If we start taking PEP 399 conformance to such levels, we might as well
stop developing CPython.

cheers

Antoine.