interface ListProps<T> {
items: T[];
renderItem: (item: T) => React.ReactNode;
}
function List<T>({ items, renderItem }: ListProps<T>) {
return <ul>{items.map((item, i) => <li key={i}>{renderItem(item)}</li>)}</ul>;
}
<List items={["a", "b"]} renderItem={(item) => <span>{item}</span>} />