# File lib/sprockets/directive_processor.rb, line 170
      def process_source
        unless @has_written_body || processed_header.empty?
          @result << processed_header << "\n"
        end

        included_pathnames.each do |pathname|
          @result << context.evaluate(pathname)
        end

        unless @has_written_body
          @result << body
        end

        if compat? && constants.any?
          @result.gsub!(/<%=(.*?)%>/) { constants[$1.strip] }
        end
      end