Nest childExpressIds (IfcCostItem) under parentExpressId as IfcRelNests.
A child already nested elsewhere is reparented.
Safe-delete an IfcCostSchedule / IfcCostItem / IfcCostValue. Throws,
naming referrers, if a value is still listed in another item's
CostValues or another value's Components — unless
options.detach is set, which rewrites those lists first. Deleting an
item detaches it from every IfcRelNests / IfcRelAssignsToControl and
cascades to values referenced ONLY by it.
Optionaloptions: { detach?: boolean }Replace itemExpressId's CostValues. Pass [] to clear it (written as $).
Assign
itemExpressIds(IfcCostItem) toscheduleExpressId(IfcCostSchedule)'s control.