Clojure - Atoms

Atoms are a data type in Clojure that provide a way to manage shared, synchronous, independent state. An atom is just pke any reference type in any other programming language. The primary use of an atom is to hold Clojure’s immutable datastructures. The value held by an atom is changed with the swap! method.

Internally, swap! reads the current value, apppes the function to it, and attempts to compare-and-set it in. Since another thread may have changed the value in the intervening time, it may have to retry, and does so in a spin loop. The net effect is that the value will always be the result of the apppcation of the suppped function to a current value, atomically.

Example

Atoms are created with the help of the atom method. An example on the same is shown in the following program.

(ns clojure.examples.example
   (:gen-class))
(defn example []
   (def myatom (atom 1))
   (println @myatom))
(example)

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