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Ruby Ruby Booleans Build a Simple Todo List Program Returning Boolean Values: Part 1

Posted by Katriel Paige
Katriel Paige
9,260 Points

Empty? method (returning Boolean values)

Okay, so I've gotten things up to this point as the syntax is fairly straightforward, but for some reason I keep getting a "bummer, try again" on this exercise. Am I missing something obvious?

Also wouldn't I get nil if there is only one item in the todo_items array?

todo_list.rb 
class TodoList
  attr_reader :name, :todo_items

  def initialize(name)
    @name = name
    @todo_items = []
  end

  def add_item(name)
    todo_items.push(TodoItem.new(name))
  end

  def empty?(name)
    if @todo_items == 0
      return true
    else @todo_items >= 1
      return false
    end
  end

end

2 Answers

Steve Hunter
Steve Hunter
57,696 Points

Hi Katriel,

I just used a straight comparison with zero. However, I don't think this fits the challenge but the code does pass. 

def empty?
  @todo_items.count == 0
end

The question isn't covering the scenario where there is one item in the array, as you say! However, the code is expecting only two outcomes; true or false, based on empty & not empty. The challenge code doesn't distinguish three states, empty; has one; has more than one.

I hope that helps,

Steve.

Steve Hunter
Steve Hunter
57,696 Points

In short, I agree with your interpretation of the question; your code reflects a solution to the question posed.

Katriel Paige
Katriel Paige
9,260 Points
Katriel Paige
Katriel Paige
9,260 Points

Oh, okay! Sometimes the questions are not always so straightforward in interpretation (because naturally I'd think you'd have to cover three cases - empty, more than one, one - based on the wording of the question) but the clarification helps in terms of the exercise. Thanks!

Steve Hunter
Steve Hunter
57,696 Points

I agree this question isn't accurately defining what code is required to pass the challenge. But, it is the correct interpretation of a helper method like empty?. That should return only two possible values; true or false. Having other states is contradictory to the purpose of this type of method.