scala is 2.10.1 but sbt console is not?

Question

I'm new to Scala/SBT, so please be gentle, but I'm trying to work my way through the SBT "Getting Started" and I noticed a discrepancy between my brew installed scala and sbt tools. When I launch the REPL for scala directly, it reports itself as Scala 2.10.1, which is what I would expect.

bobk-mbp:work bobk$ scala
Welcome to Scala version 2.10.1 (Java HotSpot(TM) 64-Bit Server VM, Java 1.7.0_17).
Type in expressions to have them evaluated.
Type :help for more information.

scala> :quit

When I launch the REPL through SBT, the REPL asserts it is 2.9.2?!?

bobk-mbp:work bobk$ sbt console
[info] Set current project to default-690573 (in build file:/Users/bobk/work/)
[info] Starting scala interpreter...
[info] 
Welcome to Scala version 2.9.2 (Java HotSpot(TM) 64-Bit Server VM, Java 1.7.0_17).
Type in expressions to have them evaluated.
Type :help for more information.

scala> :quit

What's up with that? I was expecting the build tool to use the scala environment that is hosted on my dev box. Where is it getting 2.9.2 and how do I get it to use the 2.10.1?

Both scala and sbt were installed via brew, but I don't think that really matters. The sbt version appears to be 0.12.3

bobk-mbp:work bobk$ sbt --version
sbt launcher version 0.12.3

Answer 1

Sbt downloads the scala doesnt need to have an installed one.

If you want to define something global use the ~/.sbt/global.sbt

In global.sbt you can insert scalaVersion := "2.10.1" and if you want to use your local installed version also define scalaHome := Some(file("/home/iraklis/apps/scala-2.10.1"))

For more detail visit sbt documentation (link)

Answer 2

If you start sbt with no parameters:

sbt
> ++ 2.10.1
> console

should give you Scala 2.10.1 for that session. I don't know how to make it the default for all sbt sessions without rebuilding sbt itself.