groupByMonth method

Map<String, List<Hora>> groupByMonth()

Groups dates by month.

Implementation

Map<String, List<Hora>> groupByMonth() {
  final result = <String, List<Hora>>{};
  for (final h in this) {
    final key = h.format('YYYY-MM');
    (result[key] ??= []).add(h);
  }
  return result;
}