title: var initalization at the time of declaration in scala
body: <p>I am confused with following initialization</p>
  
  <pre><code>var in = None: Option[FileInputStream]
  </code></pre>
  
  <p>however what I know is that</p>
  
  <pre><code>var varName : type = _ // default value initialization
  var varName : type = someValue // other than default intitalization
  </code></pre>
  
  <p>but what is </p>
  
  <pre><code> var in = None: Option[FileInputStream] 
  </code></pre>
  
  <p>Please help
  Thanks</p>