Hello IronPython Community,

We’re pleased to announce the release of IronPython 2.0 Release Candidate 1. We have fixed around 40 bugs since the previous beta. There have been more than 500 bug fixes since the first 2.0 alpha was announced. Apart from the bug fixes these items have also been addressed:

• The problem caused by ExtensionAttribute while using IronPython in a .NET 3.5 project that references System.Core has been fixed by moving that type to a new assembly called Microsoft.Scripting.ExtensionAttribute.dll. If you are referencing System.Core you should not reference this assembly while building it but while deploying your application, this assembly needs to be deployed as well. Harry has more details here.
• The MSI installer now has an option to ngen the installed binaries. Ngen’ing the dlls gives a significant startup performance boost. The option is turned off by default but if no issues are reported, we’ll enable it by default in a future release.
• The CPython standard library modules and packages that cannot be imported in IronPython currently have been removed from the MSI installation. The complete list is here
• The DLR sample language ToyScript is included in this release in a separate zip file. This is a temporary arrangement till the sample finds a more permanent home. For the references in the ToyScript project to line up, unzip it to the Src folder of the IronPython source release.

If no major issues with the RC are reported, we hope to ship the final 2.0 release in around a month’s time. Anyone planning to move to 2.0 please try the RC and let us know of any issues you find.