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Ruby Build a Todo List Application with Rails 4 Build a Todo List Application with Rails 4 Editing Todo Lists

David Forero
David Forero
5,492 Points
Posted by David Forero
David Forero
5,492 Points

Why do we need a todo_list variable?

Why do we need a todo_list variable?

todo_list = options[:todo_list]

4 Answers

Kenan Memis
Kenan Memis
47,314 Points
Kenan Memis
Kenan Memis
47,314 Points

Hi,

It is generally for simplicity. You can use options[:todo_list] in your code for lots of time. So using a variable as todo_list could be more readable than using options[:todo_list].

David Forero
David Forero
5,492 Points
David Forero
David Forero
5,492 Points

Also, could you please explain the syntax, why options[:todo_list]

Kenan Memis
Kenan Memis
47,314 Points
Kenan Memis
Kenan Memis
47,314 Points

options[:todo_list] syntax is usd for hashes. You know hash syntax right?

Let say if you have a hash called options = {}, you can store key and value pairs in it such as

options = { :todo_list => ["egg", "apple", "milk"], :name => "David Forero"}

From this data set if you want to have the todo_list array you have to call the hash with the key (by the way, key|value pair is written as :key => value) such as:

todo_list = options[:todo_list]

=> # ["egg", "apple", "milk"]

Is it clear now?

Alexander Lee
Alexander Lee
104 Points
Alexander Lee
Alexander Lee
104 Points

Bringing back up this question..

In this case what is options[:todo_list] value supposed to be? Based on the update_todo_list method, the options should be blank for that key value? If so, what is the purpose of this? I am a bit confused by the todo_list after using let!. Not sure why we need to to add "todo_list: todo_list" on every test either.

        ```
              options[:title] ||= "My todo list"
              options[:description] ||= "This is my todo list."
              todo_list = options[:todo_list]

              options = {:title => "My todo list, :description => "This is my todo list", :todo_list = ""}

        ```

unless :todo_list is referencing the 

        ```
        let!(:todo_list) {TodoList.create(title: "Groceries", description: "Grocery list.")}

        ```
Kevin Jenkins
Kevin Jenkins
12,630 Points
Kevin Jenkins
Kevin Jenkins
12,630 Points

Hi David,

I struggled with this line for a while as well. When a new todo list is created, we assign it to "todo_list."

When we call update_todo_list, we need to tell capybara (which runs the tests we're writing) which Edit button to press. So we pass in "todo_list" (the same one created above) into the update_todo_list function.

Then, todo_list= options[:todo_list] sets the :todo_list passed into the update_todo_list options to the local todo_list variable (on the left of the equals). Now on line within "#todo_list_#{todo_list.id}" it can get todo_list.id and select the correct edit button.

Tough to explain. Let me know if I should try again :)