IntelliJ Scala configuration issue

Question

So, I downloaded Scala and configured paths, I can run Scala console from terminal, Scala plugin is installed and "hello world" is running...

The problem is that, when I write a "hello world" program:

object First {
   def main(args: Array[String]): Unit = {
      println(12)
   }
}

it says: Cannot resolve symbol println

As I said, I can run this program and it prints out 12... Also, if I create a List or an array it "cannot resolve symbol" but everything runs with no problem at all...

In most cases I've found, there was problem with Java set up, but that's not the case here...

Answer 1

Within File->Project Structure, make sure that there is a scala library in Project Settings\Libraries Or, make sure that you have added scala-compiler.jar, scala-library.jar to your project.

If it is still acting strange, try File->Invalidate Cache/Restart

I had a similar issue with IntelliJ for an SBT project I started, with a correctly installed Scala 2.11 library, etc. Invalidate Cache fixed it so that IntelliJ could find the symbols.