Interface Selection<Item>

interface Selection<Item = object> {
    get currentState(): CurrentState<Item>;
    get isAllSelected(): boolean;
    get isIndeterminate(): boolean;
    get numSelected(): number;
    get numTotal(): number;
    get selected(): Item[];
    deselectAll(): void;
    deselectItem(item: Item): void;
    isSelected(item: Item): boolean;
    selectAll(): void;
    selectItem(item: Item): void;
    toggleAll(): void;
    toggleItem(item: Item): void;
}