title: Constructor overloading with Kotlin
body: <p>As i have one <code>User</code> class having 2 parameters : first_name, last_name. So my kotlin class with be : </p>
  
  <pre><code>data class User(val first_name:String, val last_name:String)
  </code></pre>
  
  <p>Now i want a constructor which will accept only <code>first_name</code>, or you can say just one parameter. How can i define it with <code>Kotlin</code>?</p>
  
  <p>I know we can pass default value and in that way we can ignore second parameter, but how can we write multiple constructor?</p>