 
 (setq css-indent-offset 2)
 
+(defun ar/open-in-external-app-lambda ()
+  "Return a function to open FPATH externally."
+  (cond
+   ((ar/windowsp)
+    (lambda (fPath)
+      (w32-shell-execute "open" (replace-regexp-in-string "/" "\\" fPath t t))))
+   ((ar/osxp)
+    (lambda (fPath)
+      (shell-command (format "open \"%s\"" fPath))))
+   ((ar/gnulinuxp)
+    (lambda (fPath)
+      (let ((process-connection-type nil))
+        (start-process "" nil "xdg-open" fPath))))))
+
 ;; Thank you Xah Lee.
 ;; from http://ergoemacs.org/emacs/emacs_dired_open_file_in_ext_apps.html
 (defun xah-open-in-external-app (&optional file)


(defun ar/markdown-mode-hook-function ()
  "Called when entering `markdown-mode'."
  (setq markdown-indent-on-enter nil)
  (define-key markdown-mode-map (kbd "RET") 'electric-newline-and-maybe-indent))

(ar/add-functions-to-mode-hooks '(ar/prog-mode-hook-function)
                                '(prog-mode-hook))

(setq ediff-split-window-function 'split-window-horizontally)
;; ediff-revision cleanup.
;; From http://www.emacswiki.org/emacs/DavidBoon#toc8
(defvar ar/ediff-bwin-config nil
  "Window configuration before ediff.")

(defvar ar/ediff-bwin-reg ?b
  "Register to be set up to hold ar/ediff-bwin-config configuration.")

(defun ar/ediff-bsh ()
