How to have SBT subproject with multiple Scala versions?

Question

I have a project using Scala 2.10 and one using Scala 2.11. They depend on a common project, which can compile with both.

lazy val foo = (project in file(\"foo\"         


        

Answer 1

I had a similar setup, and got it work like so:

lazy val baz = (project in file("baz")).settings(
  crossScalaVersions := Seq("2.10.4", "2.11.4")
)
lazy val bar = (project in file("bar")).dependsOn(baz).settings(
  scalaVersion := "2.10.4"
)
lazy val foo = (project in file("foo")).dependsOn(baz).settings(
  scalaVersion := "2.11.4"
)

And building with

sbt '++ 2.10.4 baz/compile' 'bar/compile' '++ 2.11.4 baz/compile' 'foo/compile'