Boo.Lang.Parser.BooLexer.mDQS_ESC C# (CSharp) Method

        protected void mDQS_ESC(bool _createToken)
        {
            int _ttype; IToken _token=null; int _begin=text.Length;
            _ttype = DQS_ESC;

            int _saveIndex = 0;
            _saveIndex = text.Length;
            match('\\');
            text.Length = _saveIndex;
            {
            switch ( cached_LA1 )
            {
            case '0':  case '\\':  case 'a':  case 'b':
            case 'f':  case 'n':  case 'r':  case 't':
            case 'u':
            {
                mSESC(false);
                break;
            }
            case '"':
            {
                match('"');
                break;
            }
            case '$':
            {
                match('$');
                break;
            }
            default:
            {
                throw new NoViableAltForCharException(cached_LA1, getFilename(), getLine(), getColumn());
            }
             }
            }
            if (_createToken && (null == _token) && (_ttype != Token.SKIP))
            {
            _token = makeToken(_ttype);
            _token.setText(text.ToString(_begin, text.Length-_begin));
            }
            returnToken_ = _token;
        }