Correct the locale of numeric digits of an address string generated from CNPostalAddressFormatter

String+CNPostalAddressFormatter.swift

import Foundation

extension String {
    
    /// Corrects the numeric digits of user-facing strings so that
    /// they appear in the correct locale of the device.
    ///
    /// For example, `CNPostalAddressFormatter` does not take into consideration the locale when 
    /// converting numerics digits. An address `"1234 King Fahd Rd."` in "en_US" locale gets
    /// converted to `"1234 طريق الملك فهد"` in "ar_SA" while it should be `"١٢٣٤ طريق الملك فهد"`.
    /// Another example is when you get a user facing string from a webservice and you want to make
    /// sure the numbers in the string are in the correct locale.
    /// - Returns: The same string after correcting the numbers locale.
    func correctingNumbersWithCurrentLocale() -> String {
        let formatter = NumberFormatter()
        var string = ""
        
        for character in self {
            if let number = formatter.number(from: String(character)) {
                string += formatter.string(from: number)!
            } else {
                string += String(character)
            }
        }
        
        return string
    }
    
    
}