After seeing it on TSS.net, I checked out the X-develop product website. X-develop is a new multi-language cross-platform IDE that supports both .NET languages like VB.NET, C# and J# as well as Java. It includes support for all the .NET 2.0 features like generics as well as new Java 5.0 features like generics, varargs, enums and boxing.

When I checked out the website, I noticed a section covering "Custom Languages". Here's another example of bias against DSLs - this time in favor of "full grown OO languages":

"The [X-develop] language plugin API is not limited to toy languages or little domain specific languages. Instead it supports full grown OO languages. In fact the support for Java, C#, J# and Visual Basic.NET is implemented as language plugins." (Emphasis added)

This reminds me of the same kind of bias that was leveled against classic VB. Classic VB was valuable primarily because it was limited in scope and capability. But what it gave up in capability it gained in productivity. Along the same lines, DSLs are valuable because they are little, because they only focus on a single problem domain.

What exactly would be the value of another "full-grown OO language"? What features would be in a new full grown language that isn't already in Java/J#, C# or VB.NET? The only feature I can think of is dynamic language support such as type inference and duck typing a la Ruby and Boo. What non-domain specific language features are you still waiting for?