title: Automatic null assert in scala
body: <p>I would like to use <code>!</code> symbol to automatically generate non-null assert in Scala. I mean that in a situation like this:</p>
  
  <pre><code>class Person(val name:String) {
    assert(name != null)  
  } 
  </code></pre>
  
  <p>all other integrity checks can be solved by having custom argument type, but null check is always required to be written again and again. Could I have just something like this?</p>
  
  <pre><code>class Person(val name:String!) // note the bang (!)
  </code></pre>
  
  <p>and have that assert be generated? Are there any simple macros?</p>