Improved incremental compilation of #scala in the
making yields 10-40x compilation speedups:
https://github.com/sbt/sbt/issues/1104#issuecomment-188529825
and
After turning on the java8 backend in Scala, our
bytecode size decreased by 50% and compile times
decreased by 75%. Amazeballs!
Actually after I truned java8 backend on I got a reduced compile time. (after changing code).
Actually we use Scala as a Improved Java, so we likely don't use so much "heavy" things.
looking forward to the reactions from people regarding compilation times when sbt 1.0 and scala 2.12 land. hope a broad spectrum of code get's these compilation time improvements.
Sure, but Scala 2.12 replaces anonymous classes with Java 8 functional interfaces. Vast reduction in generated bytecode as a result, thus, not only faster compile times but also perhaps better run time performance (though hotspot, miracle of engineering that it is, does a pretty good job of optimizing most anything you throw at it).
Saying that, Scala 2.12 will still be relatively slow compared to say, C, Go, Java and similar languages not high up on the abstraction ladder. The real compiler speed up will be coming with Dotty (Scala 3). Martin Odersky estimates that Dotty will be up to 4X faster than present day Scala.
