accepts method
Whether rule (default: root) derives exactly text.
Implementation
bool accepts(String text, {String? rule}) {
final start = rule ?? root;
if (!_rules.containsKey(start)) throw ArgumentError.value(start, 'rule', 'is not defined');
final run = _Run(_rules, text.runes.toList());
return run.rule(start, 0).contains(run.input.length);
}