I am trying to get a collection select from an another model and I keep getting the above error. Looked everywhere, got rails casts but nothing makes sense.
_form.rb
 <%= f.label :city %><br />
 <%= f.collection_select (:share ,:city_id, City.all , :id, :name ) %>
It highlights 'form' on the error report
<h1>New share</h1>
<%= render 'form' %>
<%= link_to 'Back', shares_path %>
Here are my models...
class Share
  include Mongoid::Document
  field :name, type: String
  field :type, type: String
  field :summary, type: String
  field :description, type: String
  field :city, type: String
  embedded_in :city
  has_many :category
end
class City
  include Mongoid::Document
  embedded_in :share
  field :name, type: String
  field :country, type: String
  attr_accessible :name, :city_id, :id
end
Searched everywhere and I cannot figure it out. It must be something silly.