Python or IronPython

Question

How does IronPython stack up to the default Windows implementation of Python from python.org? If I am learning Python, will I be learning a subtley different language with IronPython, and what libraries would I be doing without?

Are there, alternatively, any pros to IronPython (not including .NET IL compiled classes) that would make it more attractive an option?

Answer 1

Well, it's generally faster.

Can't use modules, and only has a subset of the library.

Here's a list of differences.

Answer 2

There are some subtle differences in how you write your code, but the biggest difference is in the libraries you have available.

With IronPython, you have all the .Net libraries available, but at the expense of some of the "normal" python libraries that haven't been ported to the .Net VM I think.

Basically, you should expect the syntax and the idioms to be the same, but a script written for IronPython wont run if you try giving it to the "regular" Python interpreter. The other way around is probably more likely, but there too you will find differences I think.

Answer 3

It also depends on whether you want your code to work on Linux. Dunno if IronPython will work on anything beside windows platforms.

Answer 4

Python is Python, the only difference is that IronPython was designed to run on the CLR (.NET Framework), and as such, can inter-operate and consume .NET assemblies written in other .NET languages. So if your platform is Windows and you also use .NET or your company does then should consider IronPython.

Answer 5

One of the pros of IronPython is that, unlike CPython, IronPython doesn't use the Global Interpreter Lock, thus making threading more effective.

In the standard Python implementation, threads grab the GIL on each object access. This limits parallel execution, which matters especially if you expect to fully utilize multiple CPUs.

Answer 6

There are a number of important differences:

1. Interoperability with other .NET languages. You can use other .NET libraries from an IronPython application, or use IronPython from a C# application, for example. This interoperability is increasing, with a movement toward greater support for dynamic types in .NET 4.0. For a lot of detail on this, see these two presentations at PDC 2008.
2. Better concurrency/multi-core support, due to lack of a GIL. (Note that the GIL doesn't inhibit threading on a single-core machine---it only limits performance on multi-core machines.)
3. Limited ability to consume Python C extensions. The Ironclad project is making significant strides toward improving this---they've nearly gotten Numpy working!
4. Less cross-platform support; basically, you've got the CLR and Mono. Mono is impressive, though, and runs on many platforms---and they've got an implementation of Silverlight, called Moonlight.
5. Reports of improved performance, although I have not looked into this carefully.
6. Feature lag: since CPython is the reference Python implementation, it has the "latest and greatest" Python features, whereas IronPython necessarily lags behind. Many people do not find this to be a problem.

Answer 7

See the blog post IronPython is a one-way gate. It summarizes some things I've learned about IronPython from asking questions on StackOverflow.

Answer 8

Pro: You can run IronPython in a browser if SilverLight is installed.