def each
      process(@initial_result).each { |doc| yield doc }
      while more?
        return kill_cursors if exhausted?
        get_more.each { |doc| yield doc }
      end
    end
def each
      process(@initial_result).each { |doc| yield doc }
      while more?
        return kill_cursors if exhausted?
        get_more.each { |doc| yield doc }
      end
    end
Iterate through documents returned from the query.

 @example Iterate over the documents in the cursor.
   cursor.each do |doc|
     ...
   end

 @return [ Enumerator ] The enumerator.

 @since 2.0.0