class Concurrent::Hash
@!macro [attach] concurrent_hash
A thread-safe subclass of Hash. This version locks against the object itself for every method call, ensuring only one thread can be reading or writing at a time. This includes iteration methods like `#each`, which takes the lock repeatedly when reading an item. @see http://ruby-doc.org/core-2.2.0/Hash.html Ruby standard library `Hash`
@!macro concurrent_hash
@!macro concurrent_hash