title: Why does a function call require the parameter name in Swift?
body: <p>I have this Function in a class:</p>
  
  <pre><code>func multiply(factor1:Int, factor2:Int) -&gt; Int{
      return factor1 * factor2
  }
  </code></pre>
  
  <p>I try to call the function using this:</p>
  
  <pre><code>var multResult = calculator.multiply(9834, 2321)
  </code></pre>
  
  <p>The problem is that the compiler wants it to look more like this:</p>
  
  <pre><code>var multResult = calculator.multiply(9834, factor2: 2321)
  </code></pre>
  
  <p>Why does the first one cause an error? </p>