is there any particular reason the style of the code can’t be changed?

@U7RJTCH6J yes there is: it's a homework assignment 🙂

Well. I created the homework assignment and I did any other functions in the same format. Would appreciate any advice :)

(defn demorgan
  [form]
  (cond
    (atom? form)
    form

    (and (= 'not (first form))
         (sequential? (second form))
         (= 'and (first (second form))))
    (let [[_ [_ & terms]] form]
      (list* 'or (map (comp #(list 'not %) demorgan) terms)))

    :else
    form))

(demorgan '(not (and x y)))
(demorgan '(not (and (not (and x y)) z)))

I suggest trying a group-by followed by a map to convert the values to a vector.

I tried group-by after I partitioned it and made a mess 🙂 group-by :artist music-collection on its own does a better job, although its not quite the right shape and artist details repeated. An anonymous function with group-by should fix it I think

This loop-recur does what I was looking for, but its so much code 🙂

(loop [albums    music-collection
       by-artist {}]
  (let [album (first albums)]
    (if (empty? albums)
      by-artist
      (recur (rest albums)
             (update by-artist
                     (keyword (:artist album))
                     conj (:album-name album))))))

hmm, loop-recur is the only approach that works so far 😞

As mentioned above you could try something like that

(reduce-kv (fn [m k v] (assoc m k (map :album-name v)))
           {}
           (group-by :artist music-collection))

The above works great, also if you wanted to do it using purely sequence function (and for example if you don't remember reduce-kv's syntax off the top of your head)

(defn artist->albums
  [coll]
  (->> coll
       (group-by :artist)
       (map (fn [[k v]]
              [k (mapv :album-name v)]))
       (into {})))

^^ is good and here's the same thing using a transducer instead of ->>.

(into {}
    (map (fn [[k v]]
           [k (mapv :album-name v)]))
    (group-by :artist music-collection))

maybe without necessity to use the function int-or-nothing

That if-let global is bad

Is just an example

if-let is in a function

probably cond-> by the looks

wait you only have a single condition there

yes, I just want to corroborate if this difference is greater than 0, and asign this value to a variable

(let [diff (- ...)]
  (when (> diff 0)
    (str diff)))

btw it's generally considered bad-form to use if-let and if without else branches. if you have no else branch use when and when-let

Thank you for that!

no worries

@UUGUA0MGQ if you don't mind, please post text instead of images, much easier to read for me anyway. To get syntax coloring you can post a snippet with Ctrl-Shift-Enter and select Clojure for the Type.

@UBRMX7MT7 okay