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Start your free trialCaleb Kleveter
Treehouse Moderator 37,862 PointsReturning boolean values: part 1.
The instructions for this challenge are as follows: "In the TodoList class, fill in the empty? method to return a boolean value. The empty? method should return true if there are no elements in the @todo_items array. The method should return false if there is more than one element in the @todo_items array."
When I run my code I get this error: "Bummer! The 'empty?' method returns false even when there are elements in the @todo_items
array."
Here is my code:
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?
if @todo_item == nil
return true
else
return false
end
end
end
I've tried to swap the return values around but I get this error: "Bummer! The empty?
method returns false when there are no elements in the @todo_items
array."
2 Answers
William Li
Courses Plus Student 26,868 PointsIn your code
def empty?
if @todo_item == nil
return true
else
return false
end
end
if @todo_item == nil
would always be evaluated to false
, even when todo_item is an empty Array; in Ruby, empty Array does not equal to nil
.
There can be many different ways to approach this problem. Here's one way to do it. You check for the length
of the @todo_items array.
def empty?
@todo_items.length == 0
end
Caleb Kleveter
Treehouse Moderator 37,862 PointsYes! I remember know, thanks for the best answer!