title: Comparing Int to Double - No Warning?
body: <p>Given the following case classes:</p>
  
  <pre><code>scala&gt; case class Foo(x: Int)
  defined class Foo
  
  scala&gt; case class Bar(x: Int)
  defined class Bar
  </code></pre>
  
  <p>The compiler shows a warning when trying to compare instances of different case classes.</p>
  
  <pre><code>scala&gt; Foo(5) == Bar(5)
  &lt;console&gt;:15: warning: comparing case class values of types Foo and Bar using `==' will always yield false
         Foo(5) == Bar(5)
                ^
  res8: Boolean = false
  </code></pre>
  
  <p>But why doesn't the following comparison give a warning?</p>
  
  <pre><code>scala&gt; (5 : Int) == (10 : Double)
  res9: Boolean = false
  </code></pre>