# File lib/tweetstream/client.rb, line 104
    def filter(query_params = {}, &block)
      [:follow, :track].each do |param|
        if query_params[param].is_a?(Array)
          query_params[param] = query_params[param].collect{|q| q.to_s}.join(',')
        elsif query_params[param]
          query_params[param] = query_params[param].to_s
        end
      end
      start('statuses/filter', query_params.merge(:method => :post), &block)
    end