[BUG]: function looking-back (XEmacs incompatibility)

[BUG]: function looking-back (XEmacs incompatibility)

[Richard KLINDA]

XEmacs and older Emacs (22 and below) don't have the function LOOKING-BACK.

I've found a definiton of it here: http://moinmo.in/EmacsForMoinMoin

,----
| (or (fboundp 'looking-back)
| ; taken straight out of http://cvs.savannah.gnu.org/viewcvs/emacs/emacs/lisp/subr.el?rev=1.530&view=auto
|     (defun looking-back (regexp &optional limit greedy)
|       "Return non-nil if text before point matches regular expression REGEXP.
| Like `looking-at' except matches before point, and is slower.
| LIMIT if non-nil speeds up the search by specifying a minimum
| starting position, to avoid checking matches that would start
| before LIMIT.
| If GREEDY is non-nil, extend the match backwards as far as possible,
| stopping when a single additional previous character cannot be part
| of a match for REGEXP."
|       (let ((start (point))
|             (pos
|              (save-excursion
|                (and (re-search-backward (concat "\\(?:" regexp "\\)\\=") limit t)
|                     (point)))))
|         (if (and greedy pos)
|             (save-restriction
|               (narrow-to-region (point-min) start)
|               (while (and (> pos (point-min))
|                           (save-excursion
|                             (goto-char pos)
|                             (backward-char 1)
|                             (looking-at (concat "\\(?:"  regexp "\\)\\'"))))
|                 (setq pos (1- pos)))
|               (save-excursion
|                 (goto-char pos)
|                 (looking-at (concat "\\(?:"  regexp "\\)\\'")))))
|         (not (null pos)))))
`----

-- 
Richard

Re: [BUG]: function looking-back (XEmacs incompatibility)

[Carsten Dominik]

Hi RIchard,

this code is already (and has been for a few weeks) in org-compat.el

- Carsten

On Dec 2, 2009, at 1:37 AM, Richard KLINDA wrote:

> XEmacs and older Emacs (22 and below) don't have the function  
> LOOKING-BACK.
>
> I've found a definiton of it here: http://moinmo.in/EmacsForMoinMoin
>
> ,----
> | (or (fboundp 'looking-back)
> | ; taken straight out of http://cvs.savannah.gnu.org/viewcvs/emacs/emacs/lisp/subr.el?rev=1.530&view=auto
> |     (defun looking-back (regexp &optional limit greedy)
> |       "Return non-nil if text before point matches regular  
> expression REGEXP.
> | Like `looking-at' except matches before point, and is slower.
> | LIMIT if non-nil speeds up the search by specifying a minimum
> | starting position, to avoid checking matches that would start
> | before LIMIT.
> | If GREEDY is non-nil, extend the match backwards as far as possible,
> | stopping when a single additional previous character cannot be part
> | of a match for REGEXP."
> |       (let ((start (point))
> |             (pos
> |              (save-excursion
> |                (and (re-search-backward (concat "\\(?:" regexp "\\) 
> \\=") limit t)
> |                     (point)))))
> |         (if (and greedy pos)
> |             (save-restriction
> |               (narrow-to-region (point-min) start)
> |               (while (and (> pos (point-min))
> |                           (save-excursion
> |                             (goto-char pos)
> |                             (backward-char 1)
> |                             (looking-at (concat "\\(?:"  regexp "\ 
> \)\\'"))))
> |                 (setq pos (1- pos)))
> |               (save-excursion
> |                 (goto-char pos)
> |                 (looking-at (concat "\\(?:"  regexp "\\)\\'")))))
> |         (not (null pos)))))
> `----
>
> -- 
> Richard
>
>
> _______________________________________________
> Emacs-orgmode mailing list
> Please use `Reply All' to send replies to the list.
> Emacs-orgmode@gnu.org
> http://lists.gnu.org/mailman/listinfo/emacs-orgmode

- Carsten

Re: [BUG]: function looking-back (XEmacs incompatibility)

[Richard KLINDA]

Superb, thanks.

>>>>> Regarding 'Re: [Orgmode] [BUG]: function looking-back (XEmacs incompatibility)'; Carsten Dominik adds:

  > Hi RIchard, this code is already (and has been for a few weeks) in
  > org-compat.el

-- 
Udv, Richard