I have converted the change into a patch made with diff and
have included it as an attachment.  The patch is relative to
Emacs version 24.3.

EIEIO supports defclass with :documentation strings, so I
think the detection of such strings should be active in both
emacs-lisp-mode and lisp-mode.

Bob


On Tue, Aug 2, 2011 at 4:01 PM, Stefan Monnier <monnier@iro.umontreal.ca> wrote:
> severity 9130 wishlist
> tags 9130 patch
> thanks
>
>> Here is a change that enhances Lisp mode fontification to handle
>> documentation of the form
>
>>     (:documentation "the doc string")
>
> Thanks.  That looks like a useful addition.  Could you try and make it
> an actual patch (as output by `diff' and friends), also could you also
> make sure your code uses a proper prefix ("lisp-") for all the functions
> it defines, and finally could you make sure it's only enabled when it's
> useful (I don't think we support such :documentation thingies in Elisp
> (tho maybe EIEIO does) so it should only be enabled in lisp-mode but
> not in emacs-lisp-mode).
>
> There's time for that: we're in feature freeze for Emacs-24.1, so we
> won't install such a change before early next year.
>
>
>         Stefan
>
>
>> These kinds of documentation forms are used in Common Lisp code for CLOS
>> class and slot documentation.
>
>> To apply the patch, replace lisp-font-lock-syntactic-face-function in
>> share/emacs/23.3/lisp/emacs-lisp/lisp-mode.el with the three functions
>> below:
>
>> (defun string-in-doc-position-p (state)
>>   (let* ((listbeg (nth 1 state))
>>          (firstsym (and listbeg
>>                         (save-excursion
>>                           (goto-char listbeg)
>>                           (and (looking-at "([ \t\n]*\\(\\(\\sw\\|\\s_\\)+\\)")
>>                                (match-string 1)))))
>>          (docelt (and firstsym (get (intern-soft firstsym)
>>                                     lisp-doc-string-elt-property))))
>>     (and docelt
>>          ;; It's a string in a form that can have a docstring.
>>          ;; Check whether it's in docstring position.
>>          (save-excursion
>>            (when (functionp docelt)
>>              (goto-char (match-end 1))
>>              (setq docelt (funcall docelt)))
>>            (goto-char listbeg)
>>            (forward-char 1)
>>            (condition-case nil
>>                (while (and (> docelt 0) (< (point) startpos)
>>                            (progn (forward-sexp 1) t))
>>                  (setq docelt (1- docelt)))
>>              (error nil))
>>            (and (zerop docelt) (<= (point) startpos)
>>                 (progn (forward-comment (point-max)) t)
>>                 (= (point) (nth 8 state)))))))
>
>> (defun string-after-documentation-keyword-p (state)
>>   (and (nth 1 state)                    ; we are inside a Lisp form
>>        (let ((startpos (nth 8 state)))
>>          (and startpos
>>               (let ((ok nil)
>>                     (prevsym (save-excursion
>>                                (goto-char startpos)
>>                                (condition-case nil
>>                                    (progn (backward-sexp 1) (setf ok t))
>>                                  (error nil))
>>                                (and ok
>>                                     (looking-at "\\(\\sw+\\)")
>>                                     (match-string 1)))))
>>                 (equal prevsym ":documentation"))))))
>
>> (defun lisp-font-lock-syntactic-face-function (state)
>>   (if (nth 3 state)
>>       ;; This might be a (doc)string or a |...| symbol.
>>       (let ((startpos (nth 8 state)))
>>         (if (eq (char-after startpos) ?|)
>>             ;; This is not a string, but a |...| symbol.
>>             nil
>>           (if (or (string-in-doc-position-p state)
>>                   (string-after-documentation-keyword-p state))
>>               font-lock-doc-face
>>             font-lock-string-face)))
>>     font-lock-comment-face))
>
>
>
>> In GNU Emacs 23.3.1 (x86_64-unknown-linux-gnu)
>>  of 2011-07-15 on paradicsom.nyc.corp.google.com
>> configured using `configure  '--prefix' '/local/software/package/emacs-23.3.1' '--without-x''
>
>> Important settings:
>>   value of $LC_ALL: nil
>>   value of $LC_COLLATE: C
>>   value of $LC_CTYPE: nil
>>   value of $LC_MESSAGES: nil
>>   value of $LC_MONETARY: C
>>   value of $LC_NUMERIC: C
>>   value of $LC_TIME: C
>>   value of $LANG: en_US.UTF-8
>>   value of $XMODIFIERS: nil
>>   locale-coding-system: utf-8-unix
>>   default enable-multibyte-characters: t
>
>> Major mode: Emacs-Lisp
>
>> Minor modes in effect:
>>   file-name-shadow-mode: t
>>   global-font-lock-mode: t
>>   font-lock-mode: t
>>   auto-encryption-mode: t
>>   auto-compression-mode: t
>>   line-number-mode: t
>
>> Recent input:
>> ESC [ > 1 ; 2 3 0 5 ; 0 c C-x C-f . e m a c s RET C-v
>> C-v C-v C-v C-v C-v C-v C-v C-v C-v C-v C-v ESC v ESC
>> v ESC v ESC v ESC v ESC v C-v C-v C-v C-v C-a C-n C-n
>> C-n C-n C-n C-n C-n C-n C-n C-n C-n C-n C-n C-n C-n
>> C-n C-n C-n C-n C-n C-n C-n C-n C-n C-n C-n C-n C-n
>> C-n C-n C-n C-n C-n C-n C-n C-n C-n C-n C-n C-n C-n
>> C-n C-n C-n C-n C-n C-n C-n C-n C-n C-n C-n C-n C-n
>> C-n C-n C-n C-n C-n C-n C-n C-n C-n C-n C-n C-n C-n
>> C-n C-n C-n C-n C-n C-n C-n C-n C-n C-n C-n C-n C-n
>> C-n C-n C-n C-n C-n C-n C-n C-n C-n C-n C-n C-n C-n
>> C-l C-v C-v C-v ESC v ESC v ESC v ESC v ESC v ESC v
>> ESC v ESC v ESC v ESC v ESC v ESC v ESC v ESC v ESC
>> v ESC v ESC v C-v C-l C-u C-u C-n C-n C-n DEL C-x SPC
>> SPC C-a C-x C-s C-v C-x C-s C-v C-v C-v C-v ESC v C-v
>> C-n C-n C-n C-n C-n C-n C-n C-n C-l C-u C-p C-p C-p
>> C-n C-n C-n C-n C-n C-n C-n C-n C-n C-n C-n C-n C-n
>> C-n C-n C-n C-n C-n C-n C-n C-n C-n C-n C-n C-n C-n
>> C-n C-n C-n C-n C-n C-n C-n C-n C-n C-n C-n C-l ESC
>> x r e p o r t - e m a c s - b u g RET
>
>> Recent messages:
>> ("emacs")
>> Loading /local/software/source-trees/emacs-jabber/jabber-autoloads.el (source)...done
>> call-interactively: Beginning of buffer [3 times]
>> Saving file /home/brown/.emacs...
>> Wrote /home/brown/.emacs
>> (No changes need to be saved)
>
>> Load-path shadows:
>> /local/software/source-trees/cc-mode/cc-fonts hides /local/software/package/emacs-23.3.1/share/emacs/23.3/lisp/progmodes/cc-fonts
>> /local/software/source-trees/cc-mode/cc-align hides /local/software/package/emacs-23.3.1/share/emacs/23.3/lisp/progmodes/cc-align
>> /local/software/source-trees/cc-mode/cc-menus hides /local/software/package/emacs-23.3.1/share/emacs/23.3/lisp/progmodes/cc-menus
>> /local/software/source-trees/cc-mode/cc-engine hides /local/software/package/emacs-23.3.1/share/emacs/23.3/lisp/progmodes/cc-engine
>> /local/software/source-trees/cc-mode/cc-mode hides /local/software/package/emacs-23.3.1/share/emacs/23.3/lisp/progmodes/cc-mode
>> /local/software/source-trees/cc-mode/cc-awk hides /local/software/package/emacs-23.3.1/share/emacs/23.3/lisp/progmodes/cc-awk
>> /local/software/source-trees/cc-mode/cc-defs hides /local/software/package/emacs-23.3.1/share/emacs/23.3/lisp/progmodes/cc-defs
>> /local/software/source-trees/cc-mode/cc-vars hides /local/software/package/emacs-23.3.1/share/emacs/23.3/lisp/progmodes/cc-vars
>> /local/software/source-trees/cc-mode/cc-styles hides /local/software/package/emacs-23.3.1/share/emacs/23.3/lisp/progmodes/cc-styles
>> /local/software/source-trees/cc-mode/cc-bytecomp hides /local/software/package/emacs-23.3.1/share/emacs/23.3/lisp/progmodes/cc-bytecomp
>> /local/software/source-trees/cc-mode/cc-compat hides /local/software/package/emacs-23.3.1/share/emacs/23.3/lisp/progmodes/cc-compat
>> /local/software/source-trees/cc-mode/cc-cmds hides /local/software/package/emacs-23.3.1/share/emacs/23.3/lisp/progmodes/cc-cmds
>> /local/software/source-trees/cc-mode/cc-langs hides /local/software/package/emacs-23.3.1/share/emacs/23.3/lisp/progmodes/cc-langs
>> /local/software/package/org-5.13e/org-publish hides /local/software/package/emacs-23.3.1/share/emacs/23.3/lisp/org/org-publish
>> /local/software/package/org-5.13e/org hides /local/software/package/emacs-23.3.1/share/emacs/23.3/lisp/org/org
>> /local/software/package/org-5.13e/org-install hides /local/software/package/emacs-23.3.1/share/emacs/23.3/lisp/org/org-install
>> /local/software/package/org-5.13e/org-mouse hides /local/software/package/emacs-23.3.1/share/emacs/23.3/lisp/org/org-mouse
>
>> Features:
>> (shadow sort mail-extr message ecomplete rfc822 mml easymenu mml-sec
>> password-cache mm-decode mm-bodies mm-encode mailcap mail-parse rfc2231
>> rfc2047 rfc2045 qp ietf-drums mailabbrev nnheader gnus-util netrc
>> time-date mm-util mail-prsvr gmm-utils wid-edit mailheader canlock sha1
>> hex-util hashcash mail-utils warnings emacsbug uniquify advice help-fns
>> advice-preload slime-autoloads regexp-opt cl cl-19 ediff-hook vc-hooks
>> lisp-float-type lisp-mode register page menu-bar rfn-eshadow timer
>> jit-lock font-lock syntax facemenu font-core frame cham georgian
>> utf-8-lang misc-lang vietnamese tibetan thai tai-viet lao korean
>> japanese hebrew greek romanian slovak czech european ethiopic indian
>> cyrillic chinese case-table epa-hook jka-cmpr-hook help simple abbrev
>> loaddefs button minibuffer faces cus-face files text-properties overlay
>> md5 base64 format env code-pages mule custom widget
>> hashtable-print-readable backquote make-network-process multi-tty emacs)
>
>