jebberjeb

(ns test-app.core)

;; true
[(boolean 0)
 (boolean "false")
 (boolean '())

 ;; false
 (boolean nil)

jebberjeb

(ns test-app.core
  (:require [clojure.pprint :refer [pprint]]))

(->> java.sql.ResultSet
     (.getMethods)
     (map method-sig)
     (pprint))

jebberjeb

(partition-by #(mod % 3) (range 1 10))
;;((1) (2) (3) (4) (5) (6) (7) (8) (9))

(partition-by #(mod % 3) (mapcat (partial repeat 3) (range 1 10)))
;;((1 1 1) (2 2 2) (3 3 3) (4 4 4) (5 5 5) (6 6 6) (7 7 7) (8 8 8) (9 9 9))

(group-by #(mod % 3) (range 1 10))
;;{1 [1 4 7], 2 [2 5 8], 0 [3 6 9]}

(group-by #(mod % 3) (mapcat (partial repeat 3) (range 1 10)))

jebberjeb

[(= (next (range 10))
    (rest (range 10)))

 (= (next '(1))   ;; => nil
    (rest '(1)))  ;; => ()

 (= (next nil)    ;; => nil
    (rest nil))]  ;; => ()

jebberjeb

(ns test-app.core)

(defn get-rand-by-n
  [n]
  (* n (rand)))

(with-redefs
  [clojure.core/rand (fn [] 2)]
  (= 6 (get-rand-by-n 3)))

jebberjeb

(ns test-app.core)

(def r (range 10))
(def s (set r))
(def v (apply vector r))

;; We can do this because set is seqable, so
;; drop-while can seq it.
(drop-while (partial > 5) s)

jebberjeb

(ns test-app.core)

;; get from a map, vector, set

(def r (range 10))
(def m (->> r
            (map (juxt (comp keyword str) identity))
            (into {})))
(def v (apply vector (keys m)))
(def s (set (keys m)))

jebberjeb

(ns cli-tools-app.core
  (:require [clojure.tools.cli :refer [cli]])
  (:gen-class))

(defn parse-args
  [args]
  (cli args
       ["-u" "--username" "PropSol API username" :default
        "rentpath@trinitypm"]
       ["-p" "--password" "PropSol API password" :default

jebberjeb

(def a-map {:foo "foozle" :bar "barzle"})

(prn "reader readable -- read-string works")
(prn a-map)
(eval (read-string (with-out-str (pr a-map))))

(println "human readable -- read-string throws")
(println a-map)
(eval (read-string (with-out-str (print a-map))))

jebberjeb

(+ Long/MAX_VALUE 1)                                                                                           
;ArithmeticException integer overflow  clojure.lang.Numbers.throwIntOverflow (Numbers.java:1388)                                 
(+ (bigint Long/MAX_VALUE) 1)                                                                                  
;9223372036854775808N