first crack at a nested route for polymorphic association

gistfile1.txt

# my solution
get '/:notable_type/:noteable_id/notes', to: "notes#index"
@notes = Note.find_by_noteable_id_and_noteable_type(params[:notable_id], params[:notable_type]) 
# notice how it doesn't matter if an invalid :notable_type is used because it will just return an empty collection of notes

# railscast solution, but doesn't catch case with nesting more than 2 deep...
def find_noteable  
  params.each do |name, value|  
    if name =~ /(.+)_id$/  
      return $1.classify.constantize.find(value)  
    end  
  end  
  nil  
end

I think dynamic finder methods like line 3 are being deprecated.