[cageface]

Scala forces you to consider your library interface more carefully. This makes it more work to build a library but I think it pays off in a cleaner, more consistent and self-documenting library. Scala makes you think a little harder in general but, in my experience, you also write better code.

All that painful refactoring and modularization that went into Rails 3 would have been a lot easier and, I suspect, less necessary if Rails had been written in Scala.

[jshen]

I think of it more in terms of natural selection. If, and this is a big if, diversity is greater in language x than in language y due to ease of trying ideas, then there is more opportunity to hit on good ideas.

[cageface]

The barrier to entry in Scala is definitely higher, and I do think this has limited its growth. To be honest, I don't think Scala is going to be the FP lang that really goes big, although I wish it were.

I just hope Scala gets enough traction that I can find real work in the language. After using it for a while languages like Ruby and Python just feel primitive.

[jshen]

I hope any of them get enough traction that I don't have to fight to code in something other than java :)