fetch_multi

Fetches data from the cache, using the given keys. If there is data in the cache with the given keys, then that data is returned. Otherwise, the supplied block is called for each key for which there was no data, and the result will be written to the cache and returned.

Options are passed to the underlying cache implementation.

Returns an array with the data for each of the names. For example:

cache.write("bim", "bam")
cache.fetch_multi("bim", "boom") {|key| key * 2 }
# => ["bam", "boomboom"]