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

Explanation of using "let!"

I did not fully understand how "let!" is being used within the following code:

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

I believe that we placed the todo_list = inside of a block { } but I am not following let!(:todo_list)

1 Answer

I was curious about this as well but I think I found a pretty good explanation.

let is lazy-evaluated: it is not evaluated until the first time the method it defines is invoked. You can use let! to force the method's invocation before each example.

Link to Example