title: swift escaping backslash doesn't work as expected
body: <p>When I print this:</p>
  
  <pre><code>print("dfi:.*\\{8766370\\}.*:6582.*")
  </code></pre>
  
  <p>the result on the log looks as expected:</p>
  
  <pre><code>&gt;&gt;&gt;&gt; dfi:.*\{8766370\}.*:6582.*
  </code></pre>
  
  <p>but when i construct the string dynamically the result looks wrong</p>
  
  <pre><code>let re = "dfi:.*" + "\\" + "{" + "\(section)" + "\\" + "}" + ".*:\(feed).*"
  print(re)
  
  &gt;&gt;&gt;&gt; dfi:.*\\{8766370\\}.*:6582.*"
  </code></pre>
  
  <p>Notice that there is a double slash in the second case "\" and I am not sure why. I tried using a single or triple slash but it prints wrong still.</p>
  
  <p><strong>EDIT - Adding code:</strong></p>
  
  <pre><code>for (section,feeds) in toPurge {
    var regex = [String]()
    for feed in feeds {
      // dfi:\{(8767514|8769411|8768176)\}.*
      let re = "dfi:.*" + "\\" + "{" + "\(section)" + "\\" + "}" + ".*:\(feed).*"
      regex.append(re)
    }
    print(regex) // looks wrong ! bug in xcode?
    for r in regex {
      print(r) // looks perfect
    }
  }
  </code></pre>