Execute Brain****/Janet

<lang Clojure>(defn clean [src]

Execute Brain****/Janet is an implementation of Brainf***. Other implementations of Brainf***.

Execute Brain****/Janet is part of RCBF. You may find other members of RCBF at Category:RCBF.

 (def valid (zipcoll "[],.+-<>" (range 8)))
 (filter valid src))

(defn make-jumps [insns]

 (var stack @[])
 (var jumps @{})
 (eachp [i insn] insns
   (case insn
     (chr "[") (array/push stack i)
     (chr "]") (put jumps i (array/pop stack))))
 (merge jumps (invert jumps)))

(defn interpret [insns jumps]

 (def tape @{})
 (var dp 0)
 (var ip 0)
 (loop [insn :iterate (get insns ip)]
   (def cur (get tape dp 0))
   (case insn
     (chr "<") (-- dp)
     (chr ">") (++ dp)
     (chr "+") (set (tape dp) (inc cur))
     (chr "-") (set (tape dp) (dec cur))
     (chr ",") (set (tape dp) (if-let [c (:read stdin 1)] (c 0) -1))
     (chr ".") (prin (string/from-bytes (tape dp)))
     (chr "[") (if (= 0 cur) (set ip (jumps ip)))
     (chr "]") (if (not= 0 cur) (set ip (jumps ip))))
   (++ ip)))

(let [insns (clean (slurp ((dyn :args) 1)))

     jumps (make-jumps insns)]
 (interpret insns jumps))</lang>

Output:

$ echo Wnarg | janet bf.janet rot13.bf
Janet