Like clojure.core/let, but logs the value of every bound symbol

let_log.clj

(defn indent [n s]
  (let [spaces (clojure.string/join (repeat n " "))]
    (->> (clojure.string/split-lines s)
         (map (partial str spaces))
         (clojure.string/join "\n"))))

(defn bound-syms [pat]
  (condp #(%1 %2) pat
    (some-fn map? vector?) (distinct (mapcat bound-syms pat))
    symbol? [pat]
    []))

(defn log-bindings [pat]
  (letfn [(log-binding [sym]
            `[(println ~(name sym))
              (println (indent 2 (with-out-str (clojure.pprint/pprint ~sym))))])]
    `(do ~@(mapcat log-binding (bound-syms pat)))))

(defmacro let-log [bvec & body]
  `(let ~(reduce (fn [bvec [pat val]]
                   (into bvec [pat val '_ (log-bindings pat)]))
                 [] (partition 2 bvec))
     ~@body))