title: "Cannot convert value of type 'NSLayoutDimension' to expected argument type NSLayoutAnchor<NSLayoutXAxisAnchor>
body: <p>I am trying to add a subview in my Swift 3 <code>tableView</code>. I want the leading anchor to be related to 0.05 x the width of my parent view( <code>tableView</code>). </p>
  
  <p>When I write the following: </p>
  
  <pre><code>modalView.leadingAnchor.constraint(equalTo:margins.widthAnchor, constant: 0.05).isActive = true
  </code></pre>
  
  <p>I get </p>
  
  <pre><code>Cannot convert value of type 'NSLayoutDimension' to expected argument type 'NSLayoutAnchor&lt;NSLayoutXAxisAnchor&gt;'
  </code></pre>
  
  <p>How can I create the desired leading constraint using <code>NSLayoutAnchor</code>? </p>