code: def to_s
        @threads.map do |t|
          [
            "#{t.name}: status=#{t.status}; alive=#{t.alive?}",
            'Vars: ' + t.thread_variables.map { |v| "#{v}=\"#{t.thread_variable_get(v)}\"" }.join('; '),
            t.backtrace.nil? ? 'NO BACKTRACE' : "  #{t.backtrace.join("\n  ")}"
          ].join("\n")
        end
      end
docs: As a text