IronPython 2.0.1 is a minor update to IronPython 2.0 which in turn is a CPython 2.5 compatible release running under the .NET platform. Our top priority for this release was improving upon performance while retaining complete backwards compatibility with IronPython 2.0. One of many notable areas we’ve improved upon is that float-integer comparisons are now 74% faster than they were in 2.0. A full report documenting changes in interpreter performance from 2.0 to 2.0.1 can be found at http://www.codeplex.com/IronPython/Wiki/View.aspx?title=IP201VsIP20Perf. A special thanks goes out to Resolver Systems for helping us in identifying areas needing performance improvements.

In addition to numerous bug fixes in our IronPython 2.6 branch that were backported to 2.0.1, we also fixed the following CodePlex bugs specifically for this release:

• 20632: can't write a len returning a uint
• 20492: TupleExpression.IsExpandable is internal, should be public
• 20605: Compiling with pyc and PySerial module
• 20616: wrong TypeError message when invoking "str.join": implicit parameter 'self' not counted
• 20623: InitializeModule needs to add refs to mscorlib/System

We’d like to thank everyone in the community who contributed to these bugs: fwereade, Eloff, neraun, and kuno.

Notes

• IronPython 2.0.1's file version is 2.0.20209
• the samples released with IronPython 2.0 should still work with 2.0.1. Download IronPython-2.0-Samples.zip from here