Function _addDate

codebase/sources/dhtmlxscheduler.js:18228–18236

(date, collection)

    }
  }
  function _addDate(date, collection) {
    if (!(date instanceof Date)) {
      throw new TypeError(String(date) + " is not Date instance");
    }
    if (!includes(collection.map(Number), Number(date))) {
      collection.push(date);
      sort(collection);
    }
  }
  function rdatesToString(param, rdates, tzid) {
    var isUTC = !tzid || tzid.toUpperCase() === "UTC";
    var header = isUTC ? "".concat(param, ":") : "".concat(param, ";TZID=").concat(tzid, ":");