Can someone explain the following code to me?

Question

I am following along with the Rails 3 in Action book, and it is talking about override to_s in the model. The code is the following:

def to_s
           


        

Answer 1

The first question mark is attribute query methods in rails. http://api.rubyonrails.org/classes/ActiveRecord/Base.html#label-Attribute+query+methods

(provided you did not overwrite / redefine that method)

It is a shorthand method to see if that attribute present or not.