Alternative cost/weight per entry

[fourth44]

Use case: a cache of document collections. Each entry can have a small or large number of documents, which can be varying in size themselves. Eviction should happen because of the memory heap being to full; so if there is 500 MB 'free' then I can either allow insertion of many small document collections or perhaps just one big collection.

Currently the 'size' of the cache is just the amount of entries (weight fixed to 1), I would like to allow the lookup function to provide arbitrary weights (float/double).

[fourth44]

I now realize that this would have been possible with CachePolicy and Evict strategies, which seem to have been removed entirely. I would agree with remark #11 (comment).

Is there any chance that revived effort (a PR to support different ordering than LRU) could be accepted, or is there consensus to only have the current efficient implementation based on LRU?
If that is the case, the website should no longer mention 'compositional cache strategies'.

Edit: I think the order of eviction is not the issue, but rather the ability to evict the LRU item at different conditions than just size > capacity. However such a different strategy would require insight in what items are currently stored (see #45 (comment)).