Tail recursive and non-tail recursive implementations of reverse and factorial in clojure

gistfile1.clj

(defn recursive-reverse [coll]
  (if (= 0 (count coll)) 
    []
    (concat (recursive-reverse (drop 1 coll)) (take 1 coll))))

(defn recursive-reverse [coll]
  (loop [coll coll
         acc []]
    (if (empty? coll)
      acc
      (recur (rest coll) (cons (first coll) acc)))))

(defn factorial [n]
  (if (zero? n)
    0
    (if (= n 1)
      1
      (* n (factorial (dec n))))))

(defn factorial [n]
  (if (zero? n)
    0
  (loop [n n
         acc 1]
      (if (= n 1)
        acc
        (recur (dec n) (* n acc))))))

there is a mistake, (factorial 0) is 1, not 0 !