private void SetText(Parser.ScannerState from, Parser.ScannerState to)
 {
     start = from.CurrentTokenIndex;
     end   = to.CurrentTokenIndex;
 }
 internal void ResetTo(Parser.ScannerState s) => Parser.ResetTo(s);
 internal void SetText(Parser.ScannerState from)
 {
     SetText(from, State);
 }