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How do I check in Swift if a variable with a datatype of URL is empty?

I'm trying to check if my url is nil or not since I have a background thread that is getting the url from my database.

I tried doing this travelURL.absoluteString == "" and travelURL != nil but the problem still persists.

I declared my variable as var travelURL: URL!

You can use if let syntax:

if let url = travelURL {
    // Here you can use url, it is not nil
} else {
   // Here url is nil 
}

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