Will this correctly retrieve 0 values? AFAIK 0 is falsey in Ruby
``` return nil unless entry ```
No, Ruby is more strict than that. Only nil and false are falsely.
Doesn't that shift the problem to caching false then :D
you can probably always just do something like:
def no_items?
!items.present?
end
def items
# something lone
end
memoize :items, ttl: 60, max_size: 10`
just makes sure the expensive operation results in a truthy value, then add some sugar for the falsey value, done.