JetBrains Meta Programming System

Question

Does anyone have any experience with the JetBrains Meta Programming System? Is MPS better than, say, developing a DSL in Ruby?

Answer 1

I don't have any personal experience with MPS, but it was mentioned on the recent episode of Herding Code with Markus Völter. Here's my understanding. MPS is a projection editor which means, instead of parsing and editing text, you are directly editing the underlining language data structure. As Markus mentions, MPS allows you to define your own language but you can also introduce new language concepts into existing languages. For example, you can add a new keyword to Java in a matter of minutes. MPS blurs the lines between internal and external DSLs and, with this, you get static typing and tool support which you wouldn't get when developing a DSL with a dynamic language like Ruby.

Answer 2

MPS is an interesting beast and has a very huge potential. The idea is simply fantastic:

• Inside an IDE (MPS) the user defines more or less visually his DSL(s)
• the IDE allows to generate not just the language itself (the runtime or what it does), but also the "tool" aka a more or less full blown IDE, that he or other users can use to edit that new language.

That being said, unfortunately at least for the actual available MPS versions, Jetbrains failed to deliver the above(at least for me) because: - it is very very hard and complicated to use - like it would not have been made by the authors of the easy to use IntelliJ. - there are just too many concepts and "ways" the user needs to learn before it's able to do something useful, and still one gets the feeling of tapping into the dark. - the IDE won't generate an IDE for you but something inside MPS too, a "Cell Based Editor" only (as of this version).

I tried MPS several times (cause the concept is so wonderful and promising), but unfortunately as of this moment I wasn't able to do something useful with it. I might be to stupid for MPS, but in the time I was just figuring out basic about MPS, I was able to deliver fully blown usable Groovy based DSL.

I'm still following MPS's evolution, and hope that one day will deliver what did initially promised, since it's such a fantastic idea.