Q:

How to set the pattern for Credit Card PAN NUMBER with regularExpresion in Swift? 

I am trying to read pan numbers from physical credit cards using Vision Framework.  For this I use a string extension for filtering the reuslts. 
Here is an example for US phone numbers:
func extractPhoneNumber() -> (Range<String. Index>, String)? { 
        let pattern = #"""
        (? x)                    # Verbose regex, allows comments
        (?: \+1-?)?               # Potential international prefix, may have -
        [(]?                     # Potential opening (
        \b(\w{3})               # Capture xxx
        [)]?                     # Potential closing )
        [\ -./]?                 # Potential separator
        (\w{3})                 # Capture xxx
        [\ -./]?                 # Potential separator
        (\w{4})\b               # Capture xxxx
        """#

        guard let range = self.range(of: pattern, options: .regularExpression, range: nil, locale: nil) else {
            // No phone number found. 
            return nil
        }

I need a different pattern for Card Pan numbers in the following form eg.  0000 0000 0000 0000
Thank you for the help!  

A:

The pattern that worked for me is:
let pattern = #"""
        \d{4} \d{4} \d{4} \d{4}
        """#

Thank you Scriptable!