acts_as_tree
============

Specify this +acts_as+ extension if you want to model a tree structure by providing a parent association and a children
association. This requires that you have a foreign key column, which by default is called +parent_id+.

class Category < ActiveRecord::Base
acts_as_tree:order => "name"
end

Example:
root
\_ child1
\_ subchild1
\_ subchild2

root = Category.create( "name" => "root" )
child1 = root.children.create( "name" => "child1" )
subchild1 = child1.children.create( "name" => "subchild1" )

root.parent # => nil
child1.parent # => root
root.children # => [child1]
root.children.first.children.first # => subchild1

Copyright (c) 2007 David Heinemeier Hansson, released under the MIT license