I might have missunderstood the question, in this case just ignore me. 


Some code from my rails app ( AR ) 

model:
class Category < ActiveRecord::Base
    belongs_to :parent, :class_name => 'Category', :foreign_key => 'parent_id'
    has_many :children, :class_name => 'Category', :foreign_key =>
'parent_id', :dependent => true
end


 @boards, @boots, @powder, @deepsnow are fixtures structured like this :

  boards 
        \_ powder
        \_ deepsnow
  boots

testcase:

  def test_tree
    
    assert_equal true, @boards.has_children?
    assert_equal false, @boots.has_children?
    
    assert_equal @boards.children,  [@powder, @deepsnow]
    assert_equal @deepsnow.parent, @boards
  
  end



On Mon, 22 Nov 2004 07:33:07 +0900, itsme213 <itsme213 / hotmail.com> wrote:
> Does rails (or active record) have any way to conveniently define and take
> advantage of the tree structure of containment?

-- 
Tobi
http://blog.leetsoft.com