@ -103,10 +103,6 @@ extension String {
return String(self[startIndex..<endIndex])
}
func substring(from: Int, to: Int) -> String {
return substring(with: Range(uncheckedBounds: (from, to)))
func nextLetterInAlphabet(for index: Int) -> String? {
guard let uniCode = UnicodeScalar(self) else {