title: How to extend a data class with toString
body: <p>I have created a data class</p>
  <pre><code>data class Something (
      val a : String,
      val b : Object,
      val c : String
  )
  </code></pre>
  <p>as later in my program, I need the string representation of this data class I tried to extend the <code>toString</code> method.</p>
  <pre><code>override fun Something.toString() : String = a + b.result() + c
  </code></pre>
  <p>The problem here is, it does not allow extending (overriding) the <code>toString</code> function, as it is not applicable to top-level functions.</p>
  <p>How to properly override/extend the toString method of a custom dataclass?</p>