useMemo example

usememo-example.js

const categories = useMemo(() => {
  return products.reduce((categories, { category }) => {
      return !category || categories.find(({ id }) => category && category.id === id)
        ? categories
        : [
            ...categories,
            {
              id: category.id,
              value: category.id,
              label: category.title,
            },
          ];
    }, [])
}, [products]);