The "Scala Worksheet" feature of the Scala IDE plugin sounds pretty nice. Apparently it's a multi-line REPL, where changes automatically get compiled & evaluated upon save. I'm having some trouble figuring out how to get it installed in my Eclipse, though. I already had an older version of Scala IDE installed, and apparently this is a fairly new feature. I tried the latest milestone, which is supposed to have it, but…
Unfortunately the Scala IDE doesn't yet work with Eclipse Juno. Eclipse made a breaking API change. It's a shame they can't provide better backward compatibility; every new Eclipse release seems to break a lot of plugins. https://github.com/scala-ide/scala-ide/pull/145
http://scala-ide.org/download/nightly.html#scala_ide_helium_...