What are the good Scala IDEs at the start of 2010?

Question

I know this is an exact duplicate, but a year has gone by and Scala seems to be a fast moving thing, so I figure it might be acceptable to ask again:

What is the bes

Answer 1

Your main options are a fully fledged IDE like IntelliJ IDEA, NetBeans or Eclipse, or a text editor with some Scala awareness like TextMate or Emacs.

Personally, I like IntelliJ the best. I've been using it for Java development for many years, especially due to its refactoring and code navigation power. The Scala plugin was quite rough to start with, but is improving constantly. It's open source, I've been contributing bug reports and a few bug fixes.

The IDE plugins have all been working hard to be ready for Scala 2.8. It's been a moving target during the last 6 months, especially given that binary compatibility was broken as new features were added. So you might update to a new build of the compiler and then wait for supporting libraries (e.g. specs, scalatest) to be updated and recompiled.

Now that the Scala 2.8 Beta is imminent these problems are less frequent.

IntelliJ implements its own parser and type inference, as it does for Java. This lets it be more tolerant of errors and to immediately understand your code as you are editing. The type inference is not complete yet. Eclipse delegates most of this work to scalac, which means it they should always agree, but the information is only regenerated when you save files and the compiler is re-run. I don't know how NetBeans works in this regard.