Question

Hi I have a question about ruby on rails

Apparently I have a statement like this:

def sort_column
    Product.column_names.include?(params[:sort]) ? params[:sort] : "name"
end

From what I read, it’s said that this method sort the column based on params[:sort] and if there no params the products will be sorted by “name”. However, I don’t understand the way this statement is written, especially the second “?”. Can someone explain it to me ?

Answer 1

This is your code, rearranged for easier understanding.

def sort_column
  cond = Product.column_names.include?(params[:sort]) 
  cond ? params[:sort] : "name"
  #  it's equivalent to this
  # if cond
  #   params[:sort]
  # else
  #   'name'
  # end
end

First question mark is part of a method name, the second one – part of ternary operator (which you should read about).