binding.clj

(ns binding
  (:import java.util.concurrent.Executors))

(def thread-pool
  (Executors/newFixedThreadPool 1))

(set-agent-send-off-executor! thread-pool)

(def counter (agent 0))

(add-tap println)

(def ^:dynamic *some-context* nil)

(tap> "start")

(defn inspect []
  (tap>
   (format "tap: thread=%s context=%s"
           (.getId (Thread/currentThread))
           *some-context*)))

(binding [*some-context* "in the agent"]
  (send-off counter (fn [& _]
                      (inspect))))

(.submit thread-pool inspect)


;; Output
;; start
;; tap: thread=43 context=in the agent
;; tap: thread=43 context=in the agent