instance method read_date_parameter_value

# File activerecord/lib/active_record/attribute_assignment.rb, line 174
    def read_date_parameter_value(name, values_hash_from_param)
      return nil if (1..3).any? {|position| values_hash_from_param[position].blank?}
      set_values = [values_hash_from_param[1], values_hash_from_param[2], values_hash_from_param[3]]
      begin
        Date.new(*set_values)
      rescue ArgumentError # if Date.new raises an exception on an invalid date
        instantiate_time_object(name, set_values).to_date # we instantiate Time object and convert it back to a date thus using Time's logic in handling invalid dates
      end
    end