 
      (even-or-odd 3)
      (even-or-odd 4)
+     (setq blb '2)
+     (even-or-odd blb)
 
      ;; cond is like switch/case in other languages
      (setq n 2)

    ;; https://www.youtube.com/watch?v=2z-YBsd5snY
;; An Introduction to Emacs Lisp - Webpage, PDF
    ;; https://harryrschwartz.com/2014/04/08/an-introduction-to-emacs-lisp.html
;; Emacs dotfiles
    ;; https://github.com/hrs/dotfiles/blob/master/emacs/.emacs.d/configuration.org
    ;; http://pages.sachachua.com/.emacs.d/Sacha.html


;; functions
    (defun say-hello()
        (message "hello!"))
        ;; call function
        (say-hello)

    (defun square(x)
        (* x x))

    (square 5)

    (defun distance-try()
        (sqrt (+ (square (- (car '(4 2)) (car '(3 5))))
                (square (- (nth 1 '(4 2)) (nth 1 '(3 5)))))))

    ;; (+ (square (- (car '(4 2)) (car '(5 3))))
    ;; (square (- (cdr '(4 2)) (cdr '(5 3))))
