Functional Programming: A PragPub Anthology

Clojure’s Solution

Clojure’s immutable data structures, managed reference types, and software transactional memory system combine to provide a model that’s both high level and much easier to use than locking concurrency. Let’s dig in with a look at an atom, which I find to be the simplest to understand of the reference types Clojure provides.

Atomic Power

As we saw in Chapter 8, ​Identity, Value, and State in Clojure​, atoms are good for managing state that’s independent and to which we want to make synchronous changes. Here, independent means we can make the change without coordinating a change to any other piece of state. Synchronous means we want to block the thread that triggered the change until it’s done.

We can create an atom out of ...