Implementing associations (a la ActiveRecord) in Data-Oriented Programming

associations.clj

;; https://guides.rubyonrails.org/association_basics.html

(def book-info {:title "Seven Habits of Highly Effective People"})
(def author {:name "Stephen Covey"
             :id "steph"})

(def association {:association-field :author-id
                  :parent-field :id})

(defn add-to [parent child association]
  (assoc child 
    (:association-field association)
    (get parent (:parent-field association))))


(add-to author book-info association)

;; {:title "Seven Habits of Highly Effective People"
;;  :author-id "steph"}