title: IDEA: viewing Scala (core) sources in a non-SBT project
body: <p>I am working on a Scala project in <strong>IDEA 2016.2.4</strong> with <strong>scala-sdk-2.11.7</strong> configured as a dependency.</p>
  
  <p>Now I want to see e.g. how Ordered.class was implemented. But when I open the class, I only see lines like</p>
  
  <pre><code>  def &lt;(that : A) : scala.Boolean = { /* compiled code */ }
  </code></pre>
  
  <p>IDEA says “Sources not found” with buttons “Download...” and “Attach Sources...”. </p>
  
  <p>Clicking on  <strong>Download...</strong> results in <strong>Sources for 'scala-library.jar' not found</strong>.</p>
  
  <p>Then I tried <strong>Attach Sources...</strong> with <a href="https://github.com/scala/scala/archive/v2.11.7.tar.gz" rel="nofollow">scala-sources-2.11.7.tar.gz</a> just to realize, that it does not like .tar.gz (but there is <a href="http://www.scala-lang.org/download/2.11.7.html#Other_resources" rel="nofollow">no source jar available</a>). </p>
  
  <p>Am I now forced to convert the project to SBT or is there any other option?</p>