By Alvin Alexander. Last updated: January 17, 2021
If you ever need to use the Scala 3 -source
option with scalac
or the SBT build.sbt file, the correct syntax is:
-source:3.1
It’s not clear from the scalac
help text how the -source
option should be used, and I just figured that out in my build.sbt file, which has these scalac
options:
scalacOptions ++= Seq( "-deprecation", // emit warning and location for usages of deprecated APIs "-explain", // explain errors in more detail "-explain-types", // explain type errors in more detail "-feature", // emit warning and location for usages of features that should be imported explicitly "-indent", // allow significant indentation. "-new-syntax", // require `then` and `do` in control expressions. "-print-lines", // show source code line numbers. "-unchecked", // enable additional warnings where generated code depends on assumptions "-Ykind-projector", // allow `*` as wildcard to be compatible with kind projector "-Xfatal-warnings", // fail the compilation if there are any warnings "-Xmigration", // warn about constructs whose behavior may have changed since version "-source:3.1" )