synchronized counter in clojure
I would do this with an atom in Clojure:
(def counter (atom 0N));; increment the counter(swap! counter inc);; read the counter@counter=> 1This is totally thread-safe, and surprisingly high performance. Also, since it uses Clojure's abitrary-precision numeric handling, it isn't vulnerable to integer overflows in the way that a volatile int can be.....
Define a global counter as an agent
(def counter (agent 0))To increase the value contained in the agent you send a function (in this case inc) to the agent:
(send counter inc)To read the current value you can use deref or the @ reader macro:
@counter ;; same as (deref counter)Agents are only one of several available reference types. You can read more about these things on the Clojure website: