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