Abstract interface class for a cached object.
Remove and return an item from the beginning of an array-like key.
Push an item onto the end an array-like key.
Decrement a key in the cache by a given amount.
Drop the given key from the cache.
Fetch a value from the cache by its key.
Check if the cache has the given key.
Increment a key in the cache by a given amount.
Fetch an item from the cache by key, and then remove it.
Store the given value in the cache by key.
Fetch a value from the cache by its key as a Safe value.