510           areaId: state.currentSelection.areaId,
529     const areaId = `${state.nextAreaId++}`;  constant
531     state.areas[areaId] = {
532       id: areaId,
542       areaId,
750     const areaId = `${state.nextAreaId++}`;  constant
752     state.areas[areaId] = {
753       id: areaId,
758     state.currentSelection = {kind: 'AREA', areaId};
761   editArea(state: StateDraft, args: {area: Area, areaId: string}): void {
763     state.areas[args.areaId] = {
764       id: args.areaId,
771   reSelectArea(state: StateDraft, args: {areaId: string, noteId: string}):
775           areaId: args.areaId,
784     const areaId = selection.areaId;  constant
785     const index = state.areas[areaId].tracks.indexOf(args.id);  constant
787       state.areas[areaId].tracks.splice(index, 1);
790           const childIndex = state.areas[areaId].tracks.indexOf(childTrack);  constant
792             state.areas[areaId].tracks.splice(childIndex, 1);
797       state.areas[areaId].tracks.push(args.id);
800           if (!state.areas[areaId].tracks.includes(childTrack)) {
801             state.areas[areaId].tracks.push(childTrack);