Emacs and Prolog

Question

I downloaded SWI Prolog today but, I am having trouble getting emacs to recognize my prolog files. I am saving my prolog files with the extension .pl however, It keeps thinking they are perl files. In my home directory I have my ./.emacs file and I have my prolog.el file. Also at the end of my ./.emacs file I appended the following:

(autoload 'run-prolog "prolog" "Start a Prolog sub-process." t)
(autoload 'prolog-mode "prolog" "Major mode for editing Prolog programs." t)
(autoload 'mercury-mode "prolog" "Major mode for editing Mercury programs." t)
(setq prolog-system 'swi)
(setq auto-mode-alist (append '(("\\.pl$" . prolog-mode)
                                ("\\.m$" . mercury-mode))
                               auto-mode-alist)

I am using this sample .emacs file: Sample Emacs File

Why will emacs not recognize my prolog file? I am not that experienced with emacs, so all help is greatly appreciated!

Actinomorphic

You don't need your own prolog.el, since Emacs comes with one (and with the corresponding autoloads). OTOH your change to auto-mode-alist looks correct and should fix your problem, so I'm not sure why it doesn't. – Pounds

Answer 1

Emacs comes pre-configured to work with Perl rather than Prolog for .pl, because Perl is much more commonplace. Add this to your .emacs to change the configuration permanently:

(add-to-list 'auto-mode-alist '("\\.\\(pl\\|pro\\|lgt\\)" . prolog-mode))

If you just want to do it once for a single file and editing session, M-x prolog-mode will do it.

Googins