Weird issue where get blocks when using an Arc<Mutex>> about lru-rs

[jeromefroe]

Hi @volfco, thanks for the issue! I'm not sure either why the first example would just hang, that seems very odd! I think you're second example is the right approach to take though as I think in the first example the mutex handle that's returned by the lock method, and used to access the underlying cache, will go out of scope at the end of the line. In which case you won't be able to access data in any subsequent steps because the lifetime of the handle has ended.