Mac: open folder by Finder from Emacs

open-finder.el

(defun open-finder-1 (dir file)
  (let ((script
		 (if file
			 (concat
			  "tell application \"Finder\"\n"
			  "    set frontmost to true\n"
			  "    make new Finder window to (POSIX file \"" dir "\")\n" 
			  "    select file \"" file "\"\n"
			  "end tell\n")
		   (concat
			"tell application \"Finder\"\n"
			"    set frontmost to true\n"
			"    make new Finder window to {path to desktop folder}\n"
			"end tell\n"))))
    (start-process "osascript-getinfo" nil "osascript" "-e" script)))


(defun open-finder ()
  (interactive)
  (let ((path (buffer-file-name))
		dir file)
	(when path
	  (setq dir (file-name-directory path))
	  (setq file (file-name-nondirectory path)))
	(open-finder-1 dir file)))
  
(defalias 'e 'open-finder)

good job