How to install an older version of scala

https://stackoverflow.com/questions/32767204/how-to-install-an-older-version-of-scala/42908943#42908943

brew search scala

then you will find all the available versions like below 

scala                     scala@2.10                scala@2.11                scalaenv                  scalariform               scalastyle
homebrew/science/scalapack                                                     Caskroom/cask/scala-ide

Then choose whichever version you want to install. say if you want to install scala 2.11 then you can do that by runnig the command like below 

brew install scala@2.11