Expressiveness Benchmark

def purchased_all_food(food, orders):
  n_food = len(food)
  unique_orders = defaultdict(set)
  for order in orders:
    unique_orders[order["buyer"]].add(order["food"])
      
  buyers = []
  for buyer, orders in unique_orders.items():
    if len(orders) == n_food:
      buyers.append(buyer)
  return buyers

def purchased_all_food(food, orders):
    n_food = len(food)
    buyers = set([order["buyer"] for order in orders])
    return [
        buyer
        for buyer in buyers
        if len(set([order["food"] for order in orders 
             if order["buyer"] == buyer])) == n_food
    ]

def purchased_all_food(food, orders):
  n_food = len(food)
  n_unique_orders = (orders
    .groupby('buyer')
    .food.unique() 
    .map(len))
  return n_unique_orders[n_unique_orders == n_food].index.values

purchased_all_food <- function(food, orders) {
  n_food <- count(food)    
  orders %>%
    group_by(buyer) %>%
    distinct(food) %>%
    count() %>%
    filter(n == n_food) %>%
    pull(buyer)
}

SELECT DISTINCT buyer
FROM orders o1
WHERE 
  (SELECT COUNT(DISTINCT food) FROM orders o2 
   WHERE o1.buyer = o2.buyer) = 
  (SELECT COUNT(*) FROM food)

.decl has_purchased(Buyer:symbol, Food:number)
has_purchased(Buyer, Food) :- orders(Buyer, Food, _).

purchased_all_food(Buyer) :-
  orders(Buyer, _, _),
  N_food = count : food(_, _),
  N_unique_orders = count : has_purchased(Buyer, _),
  N_food = N_unique_orders.

buyers: `buyer xgroup orders;
total: count food;
purchased_all_food:
  (where {(count distinct x[`food]) = total} each buyers) `buyer