OptionalcalendarOptionalchildChild IfcWorkSchedule globalIds nested under this work plan via IfcRelNests or IfcRelAssignsToControl (this record as the parent side). Empty (or absent) for a plain WorkSchedule, or a WorkPlan with no nested schedules.
Optional so a WorkScheduleInfo built without any opinion on grouping
doesn't have to populate a field it never touches. Absent and [] are
equivalent everywhere this field is read — neither the extractor nor
the serializer distinguishes "unknown/legacy" from "known and empty";
both mean "no nested schedules to write or report".
OptionalcreationOptionaldescriptionOptionaldurationOptionalfinishOptionalidentificationOptionalparentParent IfcWorkPlan globalId, when this schedule is nested under a work plan via IfcRelNests (this schedule as a RelatedObject). Undefined for a WorkPlan itself, or a WorkSchedule with no nesting parent.
OptionalpredefinedOptionalpurposeOptionalstartRoot task globalIds directly assigned via IfcRelAssignsToControl.
WorkCalendar globalIds assigned to this schedule/plan via IfcRelAssignsToControl (RelatingControl an IfcWorkCalendar). Same optional-array convention as
ScheduleTaskInfo.calendarGlobalIdsandchildScheduleGlobalIdsabove.