title: sbt compile in Compile meaning
body: <p>Can someone kindly explain what each <code>compile</code> and <code>Compile</code> mean in this cryptic sbt idiom:</p>
  
  <pre><code>compile in Compile &lt;&lt;= (compile in Compile).dependsOn(Def.task { 
    println("task is running") // or whatever code here in the body
  })
  </code></pre>