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Error "Failed to fix character"

When I embed this code in the REPL, it works fine:

(use 'clojure.contrib.seq-utils)
(defn- random-letter [] (char (+ (rand-int 26) 97)))
(defn- random-digit [] (rand-int 10))
(defn- random-password
  "Returns an 8-character password consisting of letters and digits as follows: aa1aa1aa"
  []
  (let [password (interpose '((random-digit)) (repeat 3 (repeat 2 '(random-letter))))]
    (apply str (flatten (map (fn [coll] (map eval coll)) password)))))

Now I have this code with :gen-class :implements [my.ServiceInterface]and a function with a prefix -for implementing the interface. I am unit test with Maven / Groovy / TestNG. Everything works fine with several other interfaces / Clojure implementations, but in this particular case I get this error:

java.lang.RuntimeException:
java.lang.Exception: Unable to resolve symbol: random-letter in this context (NO_SOURCE_FILE:32)

I can’t understand why. The only thing I can say is different from this function from all other functions, is that this is the only place I use quoting, i.e. '((random-digit))and '(random-letter). EDIT: This is also the only place I use eval.

" " (defn defn-). (declare random-digit random-letter) . .

, random-password, . , .

. Clojure .

: .

(ns fred.hp2010.service.ClojurePoolerService
  (:gen-class :implements [fred.hp2010.service.PoolerService])
  (:use [clojure.contrib.seq-utils :only (flatten)]))

(def dao (fred.hp2010.persistence.Repository/getDao))

(declare find-by is-taken random-password)

(defn -addPooler [this pooler] (. dao insert "POOLER" pooler))
(defn -getPoolers [this] (. dao list "poolers"))
(defn -isEmailTaken [this email] (is-taken {"email" email}))
(defn -isUsernameTaken [this username] (is-taken {"username" username}))
(defn -login [this email password] (. dao findSingle "POOLER" {"email" email "password" password}))

(defn -changePassword [this email new-password]
  (let [updated-pooler (assoc (into {} (find-by {"email" email})) "password" new-password)]
    (. dao update "POOLER" "POOLER_ID" updated-pooler)))

(defn -resetPassword [this email]
  (let [new-password (random-password)]
    (-changePassword this email new-password)
    new-password))

(defn- find-by [params] (. dao findSingle "POOLER" params))
(defn- is-taken [params] (not (nil? (find-by params))))

(defn- random-letter [] (char (+ (rand-int 26) 97)))
(defn- random-digit [] (rand-int 10))
(defn- random-password
  "Returns an 8-character password consisting of letters and digits as follows: aa1aa1aa"
  []
  (let [password (interpose '((random-digit)) (repeat 3 (repeat 2 '(random-letter))))]
    (apply str (flatten (map (fn [coll] (map eval coll)) password)))))
+5
2

, :gen-class, , - . eval . ( ) - ` (backquote) ' (quote), . , .

, eval. repeatedly, :

(defn- random-letter [] (repeatedly #(char (+ (rand-int 26) 97))))
(defn- random-digit  [] (repeatedly #(rand-int 10)))
(defn- random-password
  "Returns an 8-character password consisting of letters and digits as follows: aa1aa1aa"
  []
  (apply str
         (mapcat (fn [[n f]] (take n (f)))
                 [[2 random-letter]
                  [1 random-digit]
                  [2 random-letter]
                  [1 random-digit]
                  [2 random-letter]])))
+7

, . , 7? , , . , '(random-letter) .

, , eval. REPL, .

EDIT:

, :

(apply str (interpose (random-digit) (repeat 3 (apply str (repeat 2 (random-letter))))))

... clojure.contrib :)

str . , str apply.

, Clojure !

EDIT:

, String:

(apply str (map (fn [c] (if (= c \a) (random-letter) (random-digit))) "aanaanaa")))

, , .

+3

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