Sunday, December 28, 2008

Some nice additions to /examples

(Shed Skin is an experimental (restricted-)Python-to-C++ compiler.)

Because the set of example programs available at the Shed Skin homepage (ssprogs.tgz) hasn't changed in a while, I decided to add some nice programs to it. With some relatively simple (but as usual, important) fixes, I was able to add support for a Jpeg decompressor (!), at 1200 lines, an iPod shuffle programmer, at 600 lines, and a multi-module mastermind program, at 300 lines.

I will be adding these programs to ssprogs.tgz with 0.0.31 (or 0.1), but for now they can be found here. They should compile using Shed Skin SVN (see the note in the top of; should be run with two arguments, e.g. "python tiger1.jpg tiger1.bmp").

Thanks to ********** for sending me the jpeg decompressor, and the authors of these programs for the nice test cases!

I would have probably added more programs (and fixed more things) if I could find more interesting test cases, but these seem hard to come by. If you happen to know of any nice programs between 500 and, say, 2,000 lines that might be statically compiled, possibly after some minor changes, please let me know. Some more bug reports would also be very welcome.

Tuesday, December 02, 2008

Shed Skin 0.0.30

I have just released version 0.0.30 of Shed Skin, an experimental (restricted) Python-to-C++ compiler.

Most importantly, this release adds (efficient) support for user-defined classes in generated extension modules, which should make it much easier to integrate compiled code within larger projects. More specifically, compiled classes can now be instantiated on the CPython side, and instances can be passed freely between CPython and Shed Skin without any conversion taking place. (Instances of builtin classes are still (recursively) copied, though, at the moment..)

Another major improvement was contributed by FFAO: a new 'set' implementation, directly based on the CPython code. While I haven't tested it on many benchmarks, it is clear that is now much faster, and on one benchmark it even outperforms CPython on my system by about 35%.

Other notable changes include complex number support, mapping None to NULL instead of 0 and printing it as 'None', as well as an important type inference fix.

With support for user-defined classes in extension modules, it looks like all the major pieces are now there to do a 0.1 release. The only thing I'd really like to do before that, is to improve support for the 'os' module. Please let me know if you'd like to help out here! Hopefully, with many details out of the way, I can have another good look at type inference for 0.2..