reset method
Implementation
void reset(int pos) {
if (pos == null) {
throw new ArgumentError('pos: $pos');
}
if (pos < 0 || pos > _inputLen) {
throw new RangeError('pos');
}
_cursor = pos;
_cache = new List<Map<int, List>>.filled(252, {});
_cachePos = new List<int>.filled(252, -1);
_cacheable = new List<bool>.filled(252, false);
_ch = -1;
_errors = <GrammarParserError>[];
_expected = <String>[];
_failurePos = -1;
_startPos = pos;
_testing = -1;
_token = null;
_tokenStart = null;
if (_cursor < _inputLen) {
_ch = _input[_cursor];
}
success = true;
}