Cobra and the Dynamic Language Runtime

[pchapin]

I've been reading a little about the Dynamic Language Runtime: special support for dynamic languages on the .NET platform. I'm wondering if this is something of potential interest to Cobra. I don't know enough right now about how .NET works or how Cobra is implemented to really say.

There are links to talks about this topic here: http://blogs.msdn.com/hugunin/archive/2 ... t-pdc.aspx. One of the talks is about the future of C#. Apparently there is work on adding optional dynamic type checking to C#. Considering that Cobra currently compiles to C# that seems like a very relevant development. Maybe the minimum .NET version for Cobra should be .NET v4!

As an aside I see there is also work on adding special support for dynamic languages to the JVM: http://openjdk.java.net/projects/mlvm/

[Csaba]

Hi,
My limited information is that .NET and languages that will uses DLR is not that hard connected.
VB9 is compatible with .NET 2, and so will VB10.
But VB8 is not compatible with all parts of .NET 3.5.

Note that System.Windows.Forms is still on v2 and so is System.IO.Ports (the ultimate reason for me to use .NET instead of JVM).
Although I do hope something better than System.Windows.Forms will come, I don't expect System.IO.Ports to be reworked.
I think Cobra will have to be compatible with .NET 2 and future versions. Is that an issue to support .NET 2 - besides testing, but it should just be to run the tests that are already written.

Regards
Csaba

[Charles]

I'm fully aware of the DLR, having read about it and attended Jim H's presentation of it at the Lang.NET symposium.

Cobra is currently using System.Reflection for its dynamic binding, but will likely use DLR in place of that at some point. Also, long term, we will eventually have a pure DLR backend for Cobra. There was interest expressed in that in a poll about what people would like to see in the future. That would also give as an interactive prompt, similar to LISP, Ruby and Python.

I'm also aware of JVM's invokedynamic and I'm sure Cobra will eventually use that in the future as well. Although there is no hurry as we don't yet have a JVM backend.

Re "something better than System.Windows.Forms", that is already here: WPF - "Windows Presentation Foundation".

Cobra will maintain support for .NET 2.0 and up. If there is a need to do so, we will produce .NET 3.5 and .NET 4.0 specific Cobra compilers in addition to the one that only requires .NET 2.0 whose generics, delegates, partial classes, etc. are quite sufficient for implementing Cobra features.