Gists url handlers for GNU/Emacs

gistfile1.el

;;; URL handlers for Gists

(defvar gist-directory
  "~/.gists/")

(defvar gist-url-regex
  "^https://gist.github.com/\\(.*\\)$")

(defun gist-retrieve (id)
  (unless (file-exists-p gist-directory)
    (make-directory gist-directory))
  (let ((url (format "git@gist.github.com:%s.git" id))
        (output (concat gist-directory id)))
    (unless (file-exists-p output)
      (call-process-shell-command "git" nil nil nil "clone" url output))
    (let ((files (directory-files output t "^[^\\.]")))
      (if (= (length files) 1)
          (find-file (first files))
        (find-file output)))))

(defun gist-browse-url (url &rest args)
  (let ((case-fold-search t))
    (string-match gist-url-regex url)
    (gist-retrieve (match-string 1 url))))

(setq browse-url-browser-function
      (list (cons gist-url-regex #'gist-browse-url)
            (cons "." #'browse-url-default-browser)))