Hi. I''ve searched but with no avail for a solution to my problem. Basically, I''m trying to create a collection select on a parent-child many_to_many relationship (in this case a product has and belongs to many categories) currently, I''ve got as far as: <% form_for :product, product, :url => { :action => ''set_status'', :id => product } do |f| %> ... <% 0.upto(product.categories.size) do |i| %> <% fields_for "categories[#{i}]", product.categories[i] do |cat| %> <%= cat.collection_select( :id, @category_select_collection, :id, :select_option_text, {:prompt => ''Select category''}) %> <% end %> <% end %> ... <% end %> But I get the error: `@categories[0]'' is not allowed as an instance variable name. What''s the most ''Rails'' way to handle this? --~--~---------~--~----~------------~-------~--~----~ You received this message because you are subscribed to the Google Groups "Ruby on Rails: Talk" group. To post to this group, send email to rubyonrails-talk-/JYPxA39Uh5TLH3MbocFFw@public.gmane.org To unsubscribe from this group, send email to rubyonrails-talk-unsubscribe-/JYPxA39Uh5TLH3MbocFFw@public.gmane.org For more options, visit this group at http://groups.google.com/group/rubyonrails-talk?hl=en -~----------~----~----~----~------~----~------~--~---