Acts_as_nested_set and acts_as_threaded

Rails
1

I’m trying to use acts_as_nested_set, as modifed by Bob S. to add
threaded functionality. I’m getting the following error:

undefined method display_threads' for #<PostController:0x3ae9828> ... #{RAILS_ROOT}/app/controllers/post_controller.rb:18:inlist’

Line 18 in post_controller.rb shows:

[post_controller.rb]
def list
display_threads @posts <= line 18
@post_pages, @posts = paginate :posts, :per_page => 10, :order =>
“root_id desc, lft”
end

The display_threads method is defined in:

[post_helper.rb]
module PostHelper
def display_threads (threads)
(snipped)
end
end

My understanding is that Helper code is merged with Controller code. I
wonder then why Rails can’t find the method display_threads.

Thanks for your help.
gk