Part 3: Printing The Contact List

Code Written

We write the following code in the video. An explanation of each line follows.

contact_list.each do |contact|
  puts "Name: #{contact["name"]}"
  if contact["phone_numbers"].size > 0
    contact["phone_numbers"].each do |phone_number|
      puts "Phone: #{phone_number}"
    end
  end
  puts "-----\n"
end

Code Explanation

contact_list.each do |contact|

The contact_list variable is an array. We iterate over each contact using the each method. The array items are passed in to each iteration of the block as a contact variable.

  puts "Name: #{contact["name"]}"

Each item in the array is a hash. First, we print out the contact's name by accessing the value at the name key.

  if contact["phone_numbers"].size > 0

It is possible to enter a contact without a phone number. The phone_numbers key is a string which is an array. We check whether or not a contact has any phone numbers by checking whether or not the length of the phone_numbers array is greater than 0.

    contact["phone_numbers"].each do |phone_number|
      puts "Phone: #{phone_number}"
    end

Next, we iterate over each phone number and print it out. This only occurs if there are items in the array.

  end
  puts "-----\n"
end

Finally, we wrap up our loops.

Final Contact List Program

Our final contact list program looks like this:

def ask(question, kind="string")
  print question + " "
  answer = gets.chomp
  answer = answer.to_i if kind == "number"
  return answer
end

def add_contact
  contact = {"name" => "", "phone_numbers" => []}
  contact["name"] = ask("What is the person's name?")
  answer = ""
  while answer != "n"
    answer = ask("Do you want to add a phone number? (y/n)")
    if answer == "y"
      phone = ask("Enter a phone number:")
      contact["phone_numbers"].push(phone)
    end
  end
  return contact
end

contact_list = []

answer = ""
while answer != "n"
  contact_list.push(add_contact())
  answer = ask("Add another? (y/n)")
end

puts "---"

contact_list.each do |contact|
  puts "Name: #{contact["name"]}"
  if contact["phone_numbers"].size > 0
    contact["phone_numbers"].each do |phone_number|
      puts "Phone: #{phone_number}"
    end
  end
  puts "-----\n"
end