Comprehension Product Search

Mix.install([
  {:jason, "~> 1.4"},
  {:kino, "~> 0.9", override: true},
  {:youtube, github: "brooklinjazz/youtube"},
  {:hidden_cell, github: "brooklinjazz/hidden_cell"}
])

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Comprehension Product Search

You’re going to create a Products module that mimics searching a list of products.

Products.all_items/0

Create a Products.all_items/0 function that uses comprehensions to generate variations of items.

items should be a map with the following fields:

• name: a string of either "computer", "phone" or "tablet"
• price: A random integer between 1 and 100.

Using these values above, all_items/0 should generate 300 unique items.

[
  %{name: "computer", price: 1},
  %{name: "computer", price: 2},
  %{name: "computer", price: 3}
  ...
] = Products.all_items()

Products.search/2

Given a list of items and a keyword list of filters, use comprehensions to filter the list of items that match the given filters.

• min: The product price must be greater than or equal to this value.
• max: The product must be less than or equal to this value.
• name: The product name must be equal to this value.

all_items = Products.all_items()

[
  %{name: "computer", price: 10},
  %{name: "computer", price: 11},
  %{name: "computer", price: 12},
  %{name: "computer", price: 13},
  %{name: "computer", price: 14},
  %{name: "computer", price: 15},
] = Products.search(all_items, [min: 10, max: 15, name: "computer"])

If a filter is not provided, then do not filter based on that value.

[
  %{name: "computer", price: 10},
  %{name: "phone", price: 10},
  %{name: "tablet", price: 10},
] = Products.search(all_items, [min: 10, max: 10])

Solution Example

defmodule Products do
  def all_items do
    for name <- ["computer", "phone", "tablet"], price <- 1..100 do
      %{name: name, price: price}
    end
  end

  def search(items, filters) do
    name = Keyword.get(filters, :name)
    min = Keyword.get(filters, :min)
    max = Keyword.get(filters, :max)

    for item <- items,
        !name || item.name == name,
        !max || item.price <= max,
        !min || min <= item.price do
      item
    end
  end
end

defmodule Products do
  def all_items do
  end

  def search(items, filters) do
  end
end

Commit Your Progress

DockYard Academy now recommends you use the latest Release rather than forking or cloning our repository.

Run git status to ensure there are no undesirable changes. Then run the following in your command line from the curriculum folder to commit your progress.

$ git add .
$ git commit -m "finish Comprehension Product Search exercise"
$ git push

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