Hack/Parse Unicode Chars in Swift String with syntax \uXXXX

String+Unicode.swift

import Foundation

extension String {
    func replaceUnicodeChars () -> String {
        if self.rangeOfString("\\u") != nil {
            let pattern = "u([A-F0-9]{4})"
            do {
                let regex = try NSRegularExpression(pattern: pattern, options: .DotMatchesLineSeparators)
                let tmp = self as NSString
                var results = [String]()
                regex.enumerateMatchesInString(self, options: [], range: NSMakeRange(0, self.characters.count)) { result, flags, stop in
                    if let range = result?.rangeAtIndex(1) {
                        results.append(tmp.substringWithRange(range))
                    }
                }
                let firstMatch = regex.firstMatchInString(self, options: [], range: NSMakeRange(0, self.characters.count))
                let finalLocation = (firstMatch?.range.location)! - 1;
                let prefix = tmp.substringWithRange(NSMakeRange(0, finalLocation));
                var processedString = prefix + ""
                for unicodeStr in results {
                    let num = Int(strtoul(unicodeStr, nil, 16))
                    processedString = processedString + String(UnicodeScalar(num))
                }
                print("NEW PROCESSED STRING === \(processedString)");
                return processedString
            } catch let e as NSError {
                print("\(e.localizedDescription)")
                return self;
            }
        } else {
            return self;
        }
    }
}