Boutique Inventory

10 Points

Instructions

Alizé runs an online fashion boutique. The big annual sale is coming up, so she wants to create some functionality to help take stock of the inventory.

A single item in the inventory is represented using a custom type.

Item(
  name: "White Shirt",
  price: 40,
  quantity: 6,
)

1. Return a list of the names of the items

Implement item_names function, which takes an iterator of items and returns an iterator of their names in the same order.

[
  Item(price: 65, name: "Maxi Brown Dress", quantity: 8),
  Item(price: 50, name: "Red Short Skirt", quantity: 0),
  Item(price: 29, name: "Black Short Skirt", quantity: 4),
  Item(price: 20, name: "Bamboo Socks Cats", quantity: 7),
]
|> iterator.from_list
|> item_names
|> iterator.to_list

// -> ["Maxi Brown Dress", "Red Short Skirt", "Black Short Skirt", "Bamboo Socks Cats"]

2. Return any items that are cheap

Implement the cheap function, which takes an iterator of items and returns an iterator of items that cost less than 30.

[
  Item(price: 65, name: "Maxi Brown Dress", quantity: 8),
  Item(price: 50, name: "Red Short Skirt", quantity: 0),
  Item(price: 29, name: "Black Short Skirt", quantity: 4),
  Item(price: 20, name: "Bamboo Socks Cats", quantity: 7),
]
|> iterator.from_list
|> cheap
|> iterator.to_list

// -> [
//   Item(price: 29, name: "Black Short Skirt", quantity: 4),
//   Item(price: 20, name: "Bamboo Socks Cats", quantity: 7),
// ]

3. Return any items that are out of stock

Implement the out_of_stock function which returns any items that have no stock.

[
  Item(price: 65, name: "Maxi Brown Dress", quantity: 8),
  Item(price: 50, name: "Red Short Skirt", quantity: 0),
  Item(price: 29, name: "Black Short Skirt", quantity: 4),
  Item(price: 20, name: "Bamboo Socks Cats", quantity: 7),
]
|> iterator.from_list
|> out_of_stock
|> iterator.to_list

// -> [
//   Item(price: 50, name: "Red Short Skirt", quantity: 0),
// ]

4. Return the total stock

Implement the total_stock function which calculates the total amount of items in your storeroom:

[
  Item(price: 65, name: "Maxi Brown Dress", quantity: 8),
  Item(price: 50, name: "Red Short Skirt", quantity: 0),
  Item(price: 29, name: "Black Short Skirt", quantity: 4),
  Item(price: 20, name: "Bamboo Socks Cats", quantity: 7),
]
|> iterator.from_list
|> total_stock

// -> 19

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