title: intellij running scala script error
body: <p>anyone encountered this when running scala script >> edit configuration in intellij.</p>
  
  <p>it works if the script is inside submodule/subproject. but throws the error below on parent module.</p>
  
  <pre><code>java.lang.NoSuchMethodError: scala.reflect.internal.Definitions$definitions$.classExistentialType(Lscala/reflect/internal/Types$Type;Lscala/reflect/internal/Symbols$Symbol;)Lscala/reflect/internal/Types$Type;
      at scala.tools.nsc.symtab.classfile.ClassfileParser.processClassType$1(ClassfileParser.scala:670)
      at scala.tools.nsc.symtab.classfile.ClassfileParser.sig2type$1(ClassfileParser.scala:679)
      at scala.tools.nsc.symtab.classfile.ClassfileParser.sig2type$1(ClassfileParser.scala:709)
  </code></pre>