core.clj

(ns tob.core
  (:import (java.net Socket)
           (java.io PrintWriter InputStreamReader BufferedReader)))

(def codetalk {:name "irc.codetalk.io" :port 6667})
(def user {:name "tob" :nick "tob"})

(declare conn-handler)

(defn connect [server]
  (let [socket (Socket. (:name server) (:port server))
        in (BufferedReader. (InputStreamReader. (.getInputStream socket)))
        out (PrintWriter. (.getOutputStream socket))
        conn (ref {:in in :out out})]
    (doto (Thread. #(conn-handler conn)) (.start))
    conn))

(defn write [conn msg]
  (doto (:out @conn)
    (.println (str msg "\r"))
    (.flush)))

(defn conn-handler [conn]
  (while (nil? (:exit @conn))
    (let [msg (.readLine (:in @conn))]
      (println msg)
      (cond
       (re-find #"^ERROR :Closing Link:" msg)
       (dosync (alter conn merge {:exit true}))
       (re-find #"^PING" msg)
       (write conn (str "PONG "  (re-find #":.*" msg)))))))

(defn login [conn user]
  (write conn (str "NICK " (:nick user)))
  (write conn (str "USER " (:nick user) " 0 * :" (:name user))))

(def irc (connect codetalk))

(defn -main [& args]
  (do
    (login irc user)
    (write irc "JOIN #lobby")
    (write irc "PRIVMSG #lobby : hai! im a lisp irc bot")
    (write irc "QUIT")))

$ lein repl
REPL started; server listening on localhost port 1161
:irc.codetalk.io NOTICE AUTH :* Looking up your hostname...
:irc.codetalk.io NOTICE AUTH :* Couldn't resolve your hostname; using your IP address instead
tob.core=> ERROR :Closing Link: [88.129.144.132](Ping timeout: 37 seconds)