title: Multi-key Map in Scala
body: <p>How can I create a Map in Scala which does not only take a single parameter as key, but rather two or three.</p>
  
  <pre><code>val map = //..?
  map("abc", 1) = 1
  println(map("abc", 2)) // =&gt; null
  println(map("abc", 1)) // =&gt; 1
  </code></pre>
  
  <p>I tried using tuples as a key, but then I have to assign values like this</p>
  
  <pre><code>map(("abc", 1)) = 1
  </code></pre>
  
  <p>Can I somehow get rid of the inner parentheses?</p>