Question

I’m learning Clojure using tutorials and going through problems like 4clojure and 99 lisp problems. I do fine with solving problems, but my code always seem to come out to be a mess like the example below.

For a language as flexible as Clojure, how can a beginner learn the idiomatic ways without having somebody else hand holding along the way?

An example of my mess:

(defn intersectall [lset] 
  (when-not (empty? (first lset))
    (if (reduce #(and %1 %2) (map #(stars/member* (front lset) %) (rest lset)))
        (cons (front lset) (intersectall (cons (rest (first lset)) (rest lset))))
        (intersectall (cons (rest (first lset)) (rest lset))))))

In case you’re wondering, the function intersectall merely returns a list of the common elements in all sub-lists of input.

So for:

(def lset '((6 :pears :and)
        (3 :peaches :and 6 :peppers)
            (8 :pears :and 6 :plums)
        (:and 6 :prunes :with some :apples)))

=> (intersectall lset)
(6 :and)

This problem is from The Little Schemer pg 117.

Answer 1

If you really want to GET Clojure, I strongly recommend The Joy of Clojure book. It is written by two of the guys who know the language best next to the original creator. They explain what you can do, how you should do it, and then the whys. I don’t think it is a good FIRST book/learning experience on the language, however I think it is the required SECOND book to study from once you have your fundamentals.