title: Binary operator '<' cannot be applied to operands of type 'Double?' and 'Int'
body: <p>I'm trying to check if a number is less than 0, and is getting an error </p>
  
  <pre><code>Binary operator '&lt;' cannot be applied to operands of type 'Double?' and 'Int'
  </code></pre>
  
  <p>It works in Xcode 8, but after I migrated to Xcode 9, it doesn't work anymore. I have another project that uses the exact same code and is working in Xcode 9, I'm not sure why it doesn't work. </p>
  
  <p>Here's the code</p>
  
  <pre><code>let percent = Double(data.percent)
  if(percent==0){
    cell.lblPercent.textColor = UIColor(red: 0.0, green: 0.0, blue: 0.0, alpha: 1.0)
  } else if(percent&lt;0){ // Binary operator '&lt;' cannot be applied to operands of type 'Double?' and 'Int'
    cell.lblPercent.textColor = UIColor(red: 0.92, green: 0.0, blue: 0.047, alpha: 1.0)
  } else {
    cell.lblPercent.textColor = UIColor(red: 0.11, green: 0.66, blue: 0.019, alpha: 1.0)
  }
  </code></pre>