title: Kotlin getter / setter when using a primary constructor
body: <p>The example is from a Kotlin-course I'm doing:</p>
  
  <pre><code>class Car {
      var speed: Int = 0
          get() = field 
          set(value) {
              field = value
          }
  }
  </code></pre>
  
  <p>If I like to use a primary constructor like this:</p>
  
  <pre><code>class Car(var speed: Int)
  </code></pre>
  
  <p><strong>How would I have to write the getter / setter in that case?</strong></p>