[Dalli::Client#with][1] duck-types [ConnectionPool#with][2] so the two libraries can be used interchangeably. Latter comes in handy in a threaded environment, e.g. Puma.

[1]: https://github.com/mperham/dalli/blob/e4a006e469b8abb413bbcb75c2928e602cf7a125/lib/dalli/client.rb#L242-L245
[2]: https://github.com/mperham/connection_pool/blob/master/lib/connection_pool.rb#L55-L62