Nested Collections

What are you going to learn?

Understand how to read and manipulate nested collections
Perform operations on nested data collections

Before jumping into the lesson, you may want to read the arrays and hash content.

Arrays in Arrays

As we move forward with software, you may find that data collections start to become a little bit more complex, whether the ones we create or third-party.

Take this simple example, and try to answer the following:

nested_collection = [["burguer", "pizza", "hot dog"], ["coke", "water", "beer"]]

What would the method count on nested_collection return?
How would you access the pizza element?
How would you add another set of data?

Hash in Arrays

heroes = [{name: "Iron Man"}, {name: "Hulk"}]

What would the method count on heroes return?
How would you access the Hulk element?
How would you change "Iron Man" to "Black Widow"?

Hash with Arrays

chinese_food_box = {
  base: ["rice", "wheat noodles", "egg noodles"],
  protein: ["fish", "shrimp", "beef", "chicken"],
  toppings: ["onion", "brocoli", "peanuts", "carrot", "potato"],
  sauce: ["teriyaki", "spicy", "cilantro", "soy sauce"]
}

What would the method count on chinese_food_box return?
How would you add a extras key-pair to the chinese_food_box collection?
How would you access the peanuts element?
How would you add another topping?

Hash with Hash

pokemons = {
  pikachu: { level: 32, attacks: ["thundershock", "thunder punch", "surf"] },
  charizard: { level: 54, attacks: ["dragon claw", "blast burn", "firespin"] },
  gengar: { level: 42, attacks: ["shadow claw", "sludge bomb", "shadow ball"] },
}

What would the method count on pokemons return?
How would you add an attribute key-pair to each pokemon element?
How would you access the charizard element attacks?
How would you add another another attack for any pokemon?

Exercises

Remember we have provided a repository with a bunch of exercises for you to complete. You can find it here

You can finde them under /ruby-exercises/Module1/nested-collections.