7L7W - Clojure

day1.clj

(defn big [st n] (> (count st) n))
(println (big "lalala" 5))

(defn collection-type [col] (cond 
                              (vector? col) :vector
                              (list? col) :list
                              (map? col) :map))
(println (collection-type [1 2 3]))
(println (collection-type (list 1 2 3)))
(println (collection-type {1 2 3 4}))

()

day2.clj

(defmacro unless [tester body other]
  (list 'if (list 'not tester) body other))

(println (macroexpand '(unless condition body other)))

(unless (> 1 2) (println "unless executed") (println "not executed"))

(defprotocol Resource
  (update [this content])
  (visit [this login]))

(defrecord WebPage [url]
  Resource
  (update [this content] (str "updated " url " with " content))
  (visit [this login] (str url " visited by " login))
  )

(def google (WebPage. "www.google.es"))
              
(visit google :myself)

day3.clj

(def accounts (ref []))

(defn add [target account] (concat target account))
(defn credit [target number amount] (map #(if (= (% :number) number) (assoc % :amount (+ (% :amount) amount)) %) target))
(defn debit [target number amount] (map #(if (= (% :number) number) (assoc % :amount (- (% :amount) amount)) %) target))



(dosync (alter accounts add [{:number 12345, :amount 0}]))
(println "before " @accounts)


(dosync (alter accounts credit 12345 5))
(dosync (alter accounts credit 12345 7))
(dosync (alter accounts debit 12345 3))
(println @accounts)