defntraced.clj

(defmacro defntraced
  "Define a function with it's inputs and output logged to the console."
  [sym & body]
  (let [[_ _ [_ & specs]] (macroexpand `(defn ~sym ~@body))
        new-specs (map
                   (fn [[args body]]
                     (let [prns (for [arg args]
                                  `(js/console.log (str '~arg) "=" (pr-str ~arg)))]
                       (list
                        args
                        `(do
                           (js/console.groupCollapsed (str '~sym " " '~args))
                           ~@prns
                           (let [res# ~body]
                             (js/console.log "=>" (pr-str res#))
                             (js/console.groupEnd)
                             res#)))))
                   specs)]
    `(def ~sym (fn ~@new-specs))))