JetBrain's Meta Programming System

[Gerald Squelart]

Seems like a slow month... But I guess it's still summer holiday time
in the North and XL authors are busy with Taodyne!? :-)

I've just stumbled upon this:
http://www.i-programmer.info/news/98-languages/2927-meta-programming-system-20.html

"[MPS] allows you to work in a Domain Specific Language DSL that you
can invent as you go along."

Sounds like what XL is trying to do!

Did you guys know about it? What do you think?

[Christophe de Dinechin]

On 24 août 2011, at 00:23, Gerald Squelart wrote:

> Seems like a slow month... But I guess it's still summer holiday time
> in the North and XL authors are busy with Taodyne!? :-)

Yes, we are! This is an exciting time for us. We are focusing a lot of energy on getting results that look good and at acceptable frame rates. So the work on the compiler itself has been a bit slow, though if you look at recent revisions, you'll see that I've been somewhat active recently on type inference.

>
> I've just stumbled upon this:
> http://www.i-programmer.info/news/98-languages/2927-meta-programming-system-20.html

This looks very interesting. It's more oriented towards "high-level" stuff than XLR, but it seems to be fairly advanced and easy to use.

> "[MPS] allows you to work in a Domain Specific Language DSL that you
> can invent as you go along."
>
> Sounds like what XL is trying to do!

At a high level, yes. I'd say it's closer to what Intentional Programming is trying to achieve. XL is focusing more on a text-based approach and program transformations. For example, consider the following example http://www.jetbrains.com/mps/demos/screencast/lockstatement-language/buildingTheLanguage.html that adds a lock statement. Most of the time in that demo helps integrating "lock" statements in the IDE. It doesn't explain (as far as I can tell) how that lock statement transforms into anything useful.

In XL, you'd do something like this:

lock L:Lock, Body ->
acquire L
Body
release L

And that's basically it for adding a lock statement. We can do this all the way to machine instructions.

> Did you guys know about it? What do you think?

I didn't know about it, and it looks both quite exciting and mature. As I wrote above, it reminds me quite a bit of Intentional Programming. I would probably not use it because I find it "click-heavy", but many people will feel more comfortable with this approach than with XL because the IDE is integrated.

Thanks
Christophe