Whats the difference? Function order.

rubyonrails-talk
1

I have been baffled by this for a while? I have been going through some tutorials and got stuck on this. The following gives me an error in the view "You have a nil object when you didn't expect it" for "display_cart". It's saying the variable "@items" is nil in the view. But if i reorder the functions and put "display_cart" before "find_cart", it works. Does the order of the functions matter?

class StoreController < ApplicationController

  def index     @products = Product.salable_items   end

  def add_to_cart     product = Product.find(params[:id])     @cart = find_cart     @cart.add_product(product)     redirect_to(:action => 'display_cart')   end

  private   def find_cart     session[:cart] ||= Cart.new   end

  def display_cart     @cart = find_cart     @items = @cart.items   end

end

2

Hi --

I have been baffled by this for a while? I have been going through some tutorials and got stuck on this. The following gives me an error in the view "You have a nil object when you didn't expect it" for "display_cart". It's saying the variable "@items" is nil in the view. But if i reorder the functions and put "display_cart" before "find_cart", it works. Does the order of the functions matter?

No, but their relation to the "private" directive does. If display_cart is private, then the action won't be executed; instead, the template will be rendered directly, and since the action was skipped, @items won't be set.

So you'll need to move display_cart above "private", or declare it public. (I'd move it; it gets messy if you start declaring access for methods individually.)

David