Learning about hashes in Ruby

Question

I'm trying to figure out how to print just the key in a Hash right now. I'm still new to this and I'm missing something on how to just print the key. My code so far:

shopping_list = {
    'milk' => false,
    'eggs' => false,
    'jalapenos' => true
}

puts "Here is your shopping list!"
shopping_list.each do |key|
    puts "- #{key}"
end

My output:

Here is your shopping list!
- ["milk", false]
- ["eggs", false]
- ["jalapenos", true]

I just want to value to print out like:

Here is your shopping list!
- milk
- eggs

Eventually, I would like to leave out the true shopping item, in this instance, it would already be purchased. I would like to print out what I still need to buy first.

Answer 1

You can get values you want by combining #reject, #keys and #each methods like below:

shopping_list.reject { |key, value| value }.keys.each do |key|
  puts "- #{key}"
end

As Cary Swoveland mentioned, the code above was created temporary arrays. If you don't want to created those, you can use the code below:

shopping_list.each do |key, value|
  puts "- #{key}" if value == false
end

Answer 2

Figured it out.

shopping_list = {
    'milk' => false,
    'eggs' => false,
    'jalapenos' => true
}

puts "Here is your shopping list!"
for key in shopping_list.keys()
    puts "- #{key}"
end

My output.

Here is your shopping list!
- milk
- eggs
- jalapenos