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Ruby Ruby Booleans Build a Simple Todo List Program Returning Boolean Values: Part 2

Sophie DeBenedetto
Sophie DeBenedetto
1,233 Points
Posted by Sophie DeBenedetto
Sophie DeBenedetto
1,233 Points

contains? method

I'm having trouble defining the contains? method to check if the todo_list contains a certain element. So far I've tried it a few different ways. Below is my latest attempt. I've also tried iterating through the array and setting a contains variable to return true if the index element == the named argument. Neither way seems to be working. Any suggestions would be greatly appreciated!

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 contains?(name)
    if todo_items.include?(name)
      return true
    else
      return false
    end
  end

  def find_index(name)
    index = 0
    found = false
        todo_items.each do |item|
      found = true if item.name == name
      break if found
      index += 1
    end
    if found
      return index
    else
      return nil
    end
  end
end

2 Answers

Stone Preston
Stone Preston
42,016 Points
Stone Preston
Stone Preston
42,016 Points

hmm your code looks correct.

there is an even simpler way since the include? method itself returns a boolean is just to throw out the if/else and just call include?:

def contains?(name)
    todo_items.include?(name)
end

the above code should return true if the the array contains the parameter name, and false otherwise

however that fails as well and im not too sure why its not passing. the error says its not returning a boolean but it has to be. tried using an explicit return as well and that didnt work either.

Jason Seifer any ideas whats going on?

Jess Pendley
Jess Pendley
13,128 Points

I am having the same problem, even when using an explicit return value.

Sophie DeBenedetto
Sophie DeBenedetto
1,233 Points
Sophie DeBenedetto
Sophie DeBenedetto
1,233 Points

Got it to work by copying and slightly altering code from find_index method:

def contains?(name)
    index = 0
    contains = false
      todo_items.each do |item|
      contains = true if item.name == name
      break if contains
      index += 1
    end
    if contains
      return true
    else
      return false
    end
end

Not sure why it is necessary to create contains variable and then iterate through todo_items array though...

Jason Seifer
STAFF
Jason Seifer
Treehouse Guest Teacher
Jason Seifer
Jason Seifer
Treehouse Guest Teacher

Hey Sophie DeBenedetto, great question! Check out this answer for why the initial #contains? method didn't work.