Some keybindings for Prolog in Emacs

.emacs.d prolog.el

(defun inferior-prolog-proc ()
  (get-buffer-process (prolog-inferior-buffer)))

(defun inferior-prolog-get-clause ()
  (buffer-substring-no-properties (prolog-clause-start)
                                  (prolog-clause-end)))

(defun inferior-prolog-send-read ()
  "Send a char read from minibufer."
  (interactive)
  (let* ((char (read-char-exclusive "Char to send: "))
	 (expr (char-to-string char)))
    (comint-send-string (inferior-prolog-proc) expr)))

(defun inferior-prolog-send-clause ()
  "Send current rule."
  (interactive)
  (let* ((clause (inferior-prolog-get-clause))
         (expr (concat clause "\n")))
    (comint-send-string (inferior-prolog-proc) expr)))

(defun inferior-prolog-send-assertz-clause ()
  "Send current rule as an assertion."
  (interactive)
  (let* ((clause (buffer-substring-no-properties (prolog-clause-start)
                                                 (prolog-clause-end)))
         (expr (replace-regexp-in-string "^\\(.*\\)\\.$" "assertz(\\1).\n"
                                         clause)))
    (comint-send-string (inferior-prolog-proc) expr)))

(add-hook 'prolog-mode-hook
          (lambda ()
	    (local-set-key (kbd "C-c C-q")
                           #'inferior-prolog-send-read)
	    (local-set-key (kbd "C-c C-e")
                           #'inferior-prolog-send-clause)
            (local-set-key (kbd "C-c C-a")
                           #'inferior-prolog-send-assertz-clause)))