Re: [Fwd: Re: beginning-of-defun]

[Andreas Roehler]

Thien-Thi Nguyen schrieb:
>    From: Andreas Roehler <address@hidden>
>    Date: Mon, 10 Jul 2006 15:46:02 +0200
>
>    It's not just for fun I entered this matter. `beginning-of-defun' is
>    buggy - and a lot of forms which rely on it.
>
> given the discussion so far i remain unconvinced there is a bug.  note
> however: i'm not stopping you from continuing, personally.  if you post
> code as the way to propose the bug fix, it that will be easier to
> evaluate its merits.  remember to not break callers (both included w/
> emacs and external) of `beginning-of-defun'.
>
> thi
>
>   

There are not many, but some cases, where `beginning-of-defun'
fails

To use a real existing inner form (cursor at roof-sign):

(when (boundp 'bar)
 (defun e-r-t-l ()
   (let ((starting-point (point)))
     (end-of-defun)
     (beginning-of-defun)
     (prog1
     (edebug-read-and-maybe-wrap-form)
   ;; Recover point, but only if no error occurred.
   (goto-char starting-point)))))
                            ^

M-x eval-defun ==> nil
Evaluation fails caused by failure of (beginning-of-defun)

(defun e-r-t-l ()
 (let ((starting-point (point)))
   (end-of-defun)
   (beginning-of-defun)
   (prog1
   (edebug-read-and-maybe-wrap-form)
     ;; Recover point, but only if no error occurred.
     (goto-char starting-point))))
                          ^

M-x eval-defun ==> e-r-t-l

However, it should also work in the first case.

As I need it to call from programs, it should be possible to rely
on.

Hopeful to send some scratch next days.
__
Andreas Roehler