Rails Ruby on Rails

% rails -v
Rails 3.0.0.beta
% ruby -v
ruby 1.9.2dev (2010-02-03 trunk 26544) [x86_64-darwin10.2.0]

% rails g scaffold post data:text
% rake db:migrate

# add serialize to Post
% cat app/models/post.rb
class Post < ActiveRecord::Base
  serialize :data
end

# add class to store in data field
% cat lib/like_a_model.rb 
class LikeAModel
  extend ActiveModel::Naming
  include ActiveModel::Validations
  include ActiveModel::Serialization

  attr_accessor :attributes
  
  def initialize(attributes = {})
    @attributes = HashWithIndifferentAccess.new(attributes)
  end
 
  def read_attribute_for_validation(key)
    @attributes[key]
  end
  
  def to_model
    self
  end

  def valid?()      true end
  def new_record?() true end
  def destroyed?()  true end

  def errors
    obj = Object.new
    def obj.[](key)         [] end
    def obj.full_messages() [] end
    obj
  end
end

% rc
Loading development environment (Rails 3.0.0.beta)
irb(main):001:0> a = LikeAModel.new(:abc => 123, :def => 456)
=> #<LikeAModel:0x00000100edadb8 @attributes={"abc"=>123, "def"=>456}>
irb(main):002:0> b = Post.create(:data => a)
=> #<Post id: 1, data: #<LikeAModel:0x00000100edadb8 @attributes={"abc"=>123, "def"=>456}>, created_at: "2010-02-17 22:10:07", updated_at: "2010-02-17 22:10:07">
irb(main):003:0> x = Post.first
=> #<Post id: 1, data: #<LikeAModel:0x00000102381500 @attributes={"abc"=>123, "def"=>456}>, created_at: "2010-02-17 22:10:07", updated_at: "2010-02-17 22:10:07">
irb(main):004:0> x.data
=> #<LikeAModel:0x00000102381500 @attributes={"abc"=>123, "def"=>456}>
irb(main):008:0> raise x.data.inspect
RuntimeError: #<LikeAModel:0x00000102381500 @attributes={"abc"=>123, "def"=>456}>

everything looking good so far.

now i add x = Post.first; raise x.data.inspect to a view and receive a YAML::Object instead -

RuntimeError in PostsController#index
#<YAML::Object:0x00000100e65270 @class="LikeAModel", @ivars={"attributes"=>{"abc"=>123, "def"=>456}}>

and if i attempt to pass x.data to a form builder i get -

undefined method `model_name' for "LikeAModel":String