rails/rails — pull request #12561 by MasterLambaster (2013-10-16 16:17:59+00:00)
Title: Accept Proc as Cache#Entry expires_in option

Allow passing a proc as expires_in option for cache entry.
One of the main reasons is to allow passing dynamic expiration time for `caches_action` that can't be changed after server start or any other store options that's passed as is to cache stored adapter.