Reduce d'une liste de dates, renvoie une chaîne de concaténation des dates: date1, date2, ..., dateN

reduce.ts

/**
  Exemple de reduce d'une liste de dates (dates_obj : [{date: 'date'}, ...]
*/
reduce(row): string {
  dates = row.dates_obj.reduce<string>((previousValue, currentValue, currentIndex) => {
      let currentDate = `${dp.transform(currentValue.date, 'dd/MM/yyyy')}`;
      const { hh, mm } = { hh: dp.transform(currentValue.date, 'HH'), mm : dp.transform(currentValue.date, 'mm')};
      if (hh !== '00') {
        currentDate = `${currentDate} à ${hh}h${mm}`;
      }
      return currentIndex === 0 ? currentDate : `${previousValue}, ${currentDate}`;
    }, '');
  
  return dates;
}