With Microsoft touting its dynamic language support with technologies such as IronPython and IronRuby, a developer in Sweden named Fredrik Holmstrom is working toward the 0.1 release of a project known as IronJS, which will do for JavaScript what the aforementioned technologies did for Python and Ruby.
IronJS is an implementation of JavaScript for the .NET Common Language Runtime (CLR), just as IronPython and IronRuby are implementations of Python and Ruby on the CLR.
In a Jan. 22 blog post about the performance of IronJS, Holmstrom wrote: “I’ve measured the performance compared to another JavaScript implementation available for the .NET CLR-Jint, which is not running on the DLR but is a custom interpreted runtime.”
The DLR is Microsoft’s Dynamic Language Runtime, and it consists of a set of services that run on top of the CLR and are used to implement dynamic languages on the .NET Framework.
Regarding overall performance of IronJS, Holmstrom said:
“All in all I’m happy with the performance of IronJS, considering that I have not spent a single second optimizing it and have made conscious decisions to not use several DLR optimization techniques to keep the code as simple as possible up until the 0.1 release.”
Microsoft has hired expertise to help build up its dynamic language support. The company hired Jim Hugunin, a Python expert, to bring his IronPython project in-house, and Microsoft later hired Ruby expert John Lam to focus on the IronRuby work. Lam recently left the team to work on a new project at Microsoft.
For its part, Microsoft could conceivably be interested in an implementation of JavaScript on .NET. However, earlier plans to deliver Managed JScript on the DLR fizzled. JScript is Microsoft’s flavor of ECMAScript, which is basically the formal name for JavaScript.
Meanwhile, in a separate post, Holmstrom said IronJS now compiles jQuery 1.4, the latest version of the popular JavaScript library. jQuery creator John Resig and the jQuery team released jQuery 1.4 on Jan. 14.