expire property necessary?

[edvardchen]

Since we have kept reference of timeout handle, is it necessary to add expire as a property and check it every time we call get method? Is not obvious that it exists means it is not expired? Any other uses ?

[karladler]

I would like to have the option to set TTL without adding a timeout function. So the cache invalidation is handled on the next get request. For that kind of purpose the expiration field would be very useful, but for now I also don't see the purpose for that, except for debugging.