MPS => Scala

are you talking about generating scala code out of MPS models? if yes, it works, just use TextGen or GText as shown in those screencasts (they actually show how to generate ruby code, which is quite similar to generating scala code):

http://tv.jetbrains.net/videocontent/mps-basics-generating-text-with-textgen
http://tv.jetbrains.net/videocontent/mps-basics-gtext-generation

regards,

phil

Hi Phil
Thanks for the tip.
This is what I had in mind.

Regards, Andrey

Sorry for my ignorance of MPS, but what do you need it for when you have a language as flexible and DSL-capable as Scala?

Indeed, Scala is a pretty powerful player in the DSL arena, both due to its flexible syntax and thanks to Scala parser combinators.  
While I can't comment on Andrey's case specifically, in general, I can think of these four cases when MPS could help you move beyond what Scala can do:

• you may need to generate code for other platforms than JVM
  
• you'd like to get a complete IDE support for your DSLs, such as code completion, custom type-checking, refactorings, static code analysis, dataflow analysis
  
• you want to go wild with the syntax - e.g. tables, more positional or graphical-like notations
  
• you may need to modularize your family of DSLs - the languages can extend or embed one another and your users may further customize the languages to their own needs.