Remove println() for release version iOS Swift

Question

I would like to globally ignore all println() calls in my Swift code if I am not in a Debug build. I can't find any robust step by step instructions for this and would appreciate guidance. is there a way to do this globally, or do I need to surround every println() with #IF DEBUG/#ENDIF statements?

Answer 1

As noted, i am a student and need things defined a little more clearly to follow along. After lots of research, the sequence I needed to follow is:

Click on the project name at the top of the File Navigator at the left of the Xcode project window. This is line that has the name of the project, how many build targets there are, and the iOS SDK version.

Choose the Build Settings tab and scroll down to the "Swift Compiler - Custom Flags" section near the bottom. Click the Down Arrow next to Other Flags to expand the section.

Click on the Debug line to select it. Place your mouse cursor over the right side of the line and double-click. A list view will appear. Click the + button at the lower left of the list view to add a value. A text field will become active.

In the text field, enter the text -D DEBUG and press Return to commit the line.

Add a new Swift file to your project. You are going to want to make a custom class for the file, so enter text along the lines of the following:

class Log {

  var intFor : Int

  init() {
    intFor = 42
   }

  func DLog(message: String, function: String = __FUNCTION__) {
    #if DEBUG
      println("\(function): \(message)")
    #endif
  }
}

I was having trouble getting the class to be accepted by Xcode today, so the init may be a bit more heavyweight than necessary.

Now you will need to reference your custom class in any class in which you intend to use the new custom function in place of println() Add this as a property in every applicable class:

   let logFor = Log()

Now you can replace any instances of println() with logFor.DLog(). The output also includes the name of the function in which the line was called.

Note that inside class functions I couldn't call the function unless I made a copy of the function as a class function in that class, and println() is also a bit more flexible with the input, so I couldn't use this in every instance in my code.