Feature Request: Auto-jumping to source file (.el) upon elisp error

Feature Request: Auto-jumping to source file (.el) upon elisp error

[Nordlöw]

My highest priority Emacs feature request:

When I encounter an error in elisp code I always wonder: Is there a
way for Emacs to automatically split my elisp-error window in two and
replace one of the windows with the relating source file and jump to
position in that buffer where the error occurrred, like we are used to
with practically all other languages/IDEs?

Thanks in advance,
Nordlöw

Re: Feature Request: Auto-jumping to source file (.el) upon elisp error

[Stefan Kamphausen]

Hi,

"Nordlöw" <per.nordlow@gmail.com> writes:

> My highest priority Emacs feature request:
>
> When I encounter an error in elisp code I always wonder: Is there a
> way for Emacs to automatically split my elisp-error window in two and
> replace one of the windows with the relating source file and jump to
> position in that buffer where the error occurrred, like we are used to
> with practically all other languages/IDEs?

to me it seems that just the right thing happens.

For example, when I start a un-customized emacs:

shell> emacs -q

put the following into my scratch buffer:
----------------------------------------------------------------------
(defun produce-an-error ()
  (interactive)
  (goto-char))

(setq debug-on-error t)

(produce-an-error)
----------------------------------------------------------------------

and do a M-x eval-current-buffer I get a second window showing a
backtrace:
----------------------------------------------------------------------
Debugger entered--Lisp error: (wrong-number-of-arguments goto-char 0)
  (goto-char)
  produce-an-error()
  eval-current-buffer()
  call-interactively(eval-current-buffer)
  execute-extended-command(nil)
  call-interactively(execute-extended-command)
----------------------------------------------------------------------

The cute thing is that all known elisp functions (as opposed to
C-builtins) will be clickable to jump to the function definition.
Since I may be interested in various levels of the whole backtrace
this is way better than having the program decide which one will be my
point of interest.

Just my 2ct.

Regards,
Stefan
-- 
Stefan Kamphausen --- http://www.skamphausen.de
a blessed +42 regexp of confusion (weapon in hand)
You hit. The format string crumbles and turns to dust.

Re: Feature Request: Auto-jumping to source file (.el) upon elisp error

[Nordlöw]

On Dec 10, 10:59 am, Stefan Kamphausen <ska...@gmx.net> wrote:
> Hi,
>
> "Nordlöw" <per.nord...@gmail.com> writes:
> > My highest priority Emacs feature request:
>
> > When I encounter an error in elisp code I always wonder: Is there a
> > way for Emacs to automatically split my elisp-error window in two and
> > replace one of the windows with the relating source file and jump to
> > position in that buffer where the error occurrred, like we are used to
> > with practically all other languages/IDEs?
>
> to me it seems that just the right thing happens.
>
> For example, when I start a un-customized emacs:
>
> shell> emacs -q
>
> put the following into my scratch buffer:
> ----------------------------------------------------------------------
> (defun produce-an-error ()
>   (interactive)
>   (goto-char))
>
> (setq debug-on-error t)
>
> (produce-an-error)
> ----------------------------------------------------------------------
>
> and do a M-x eval-current-buffer I get a second window showing a
> backtrace:
> ----------------------------------------------------------------------
> Debugger entered--Lisp error: (wrong-number-of-arguments goto-char 0)
>   (goto-char)
>   produce-an-error()
>   eval-current-buffer()
>   call-interactively(eval-current-buffer)
>   execute-extended-command(nil)
>   call-interactively(execute-extended-command)
> ----------------------------------------------------------------------
>
> The cute thing is that all known elisp functions (as opposed to
> C-builtins) will be clickable to jump to the function definition.
> Since I may be interested in various levels of the whole backtrace
> this is way better than having the program decide which one will be my
> point of interest.
>
> Just my 2ct.
>
> Regards,
> Stefan
> --
> Stefan Kamphausen ---http://www.skamphausen.de
> a blessed +42 regexp of confusion (weapon in hand)
> You hit. The format string crumbles and turns to dust.

But the top-most function, in your case produce-an-error(), is neither
clickable nor mentioned about its file/buffer-origin in the Debugger
output. This is sad because this is what the user/developer wants to
see first in order to most easily understand the top-most (call-stack)
context of the problem.

/Nordlöw

Re: Feature Request: Auto-jumping to source file (.el) upon elisp error

[Stefan Kamphausen]

Hi,

"Nordlöw" <per.nordlow@gmail.com> writes:

> But the top-most function, in your case produce-an-error(), is neither
> clickable nor mentioned about its file/buffer-origin in the Debugger
> output. This is sad because this is what the user/developer wants to
> see first in order to most easily understand the top-most (call-stack)
> context of the problem.

you are right that the function is not clickable in the backtrace if
being added interactively.  It does work however, if it was written
into a separate file and then loaded via (e.g.) M-x load-file.

Does that fit your needs?

Regards,
Stefan
-- 
Stefan Kamphausen --- http://www.skamphausen.de
a blessed +42 regexp of confusion (weapon in hand)
You hit. The format string crumbles and turns to dust.

Re: Feature Request: Auto-jumping to source file (.el) upon elisp error

[Nordlöw]

On Dec 10, 1:14 pm, Stefan Kamphausen <ska...@gmx.net> wrote:
> Hi,
>
> "Nordlöw" <per.nord...@gmail.com> writes:
> > But the top-most function, in your case produce-an-error(), is neither
> > clickable nor mentioned about its file/buffer-origin in the Debugger
> > output. This is sad because this is what the user/developer wants to
> > see first in order to most easily understand the top-most (call-stack)
> > context of the problem.
>
> you are right that the function is not clickable in the backtrace if
> being added interactively.  It does work however, if it was written
> into a separate file and then loaded via (e.g.) M-x load-file.
>
> Does that fit your needs?
>
> Regards,
> Stefan
> --
> Stefan Kamphausen ---http://www.skamphausen.de
> a blessed +42 regexp of confusion (weapon in hand)
> You hit. The format string crumbles and turns to dust.

Okey, thanks for your answer!

Is it still possible to make Emacs automatically open top-most source
code context in another window?

Thanks again,
Nordlöw

Re: Feature Request: Auto-jumping to source file (.el) upon elisp error

[Andreas Röhler]

Am Montag, 10. Dezember 2007 15:27 schrieb Nordlöw:
> On Dec 10, 1:14 pm, Stefan Kamphausen <ska...@gmx.net> wrote:
> > Hi,
> >
> > "Nordlöw" <per.nord...@gmail.com> writes:
> > > But the top-most function, in your case produce-an-error(), is neither
> > > clickable nor mentioned about its file/buffer-origin in the Debugger
> > > output. This is sad because this is what the user/developer wants to
> > > see first in order to most easily understand the top-most (call-stack)
> > > context of the problem.
> >
> > you are right that the function is not clickable in the backtrace if
> > being added interactively.  It does work however, if it was written
> > into a separate file and then loaded via (e.g.) M-x load-file.
> >
> > Does that fit your needs?
> >
> > Regards,
> > Stefan
> > --
> > Stefan Kamphausen ---http://www.skamphausen.de
> > a blessed +42 regexp of confusion (weapon in hand)
> > You hit. The format string crumbles and turns to dust.
>
> Okey, thanks for your answer!
>
> Is it still possible to make Emacs automatically open top-most source
> code context in another window?
>
> Thanks again,
> Nordlöw

I use an adapted function `aktualisieren', which takes
arguments as C-h f does, but then opens the source if
available, narrowed to function mentioned. Code below.

Might that be a step forward?

Andreas Röhler

(defun aktualisieren (function)
  "Go to FUNCTION (a symbol), narrow to region."
  (interactive
   (let ((fn (save-excursion
	       (beginning-of-defun)
	       (forward-word 2)
	       (if (featurep 'xemacs)
		   (function-at-point)
		 (function-called-at-point))))
	 val)
     (list (intern-soft (completing-read (if fn
					     (format "Describe function (default %s): " fn)
					   "Describe function: ")
					 obarray 'fboundp t nil nil (symbol-name fn))))))
  (if (file-readable-p
       ;; No effect, why?
       (condition-case nil
	   (symbol-file function)
	 (error "Keine Quelldatei gefunden")))
      (let* ((datei (symbol-file function)))
	(cond
	 ((file-exists-p (concat (file-name-sans-extension datei) ".el"))
	  (find-file (concat (file-name-sans-extension datei) ".el")))
	 ((file-exists-p (concat (file-name-sans-extension datei) ".el.gz"))
	  (find-file (concat (file-name-sans-extension datei) ".el.gz")))
	 ((file-exists-p (concat datei ".gz"))
	  (find-file (concat datei ".gz")))
	 (t (error (concat "Keine Quelle vorhanden"))))
	;; 2007-06-03 a.roehler@web.de changed section end	
	(widen)
	(goto-char (point-min))
	(cond 
	 ((search-forward (concat "(defun " (symbol-name function)" ") nil t) ;; 
Leerzeichen, um "-" in Funktionsnamen auszuschlie��ßen
	  (progn
	    (narrow-to-region (progn (beginning-of-defun) (point))(progn 
(end-of-defun) (point)))
	    (delete-other-windows))) 
	 ((progn (goto-char (point-min))
		 (re-search-forward (concat "(defalias '" (symbol-name 
function) " '\\([^)]+\\)") nil t 1))
	  (progn
	    (message " %s" (match-string-no-properties 1))
	    (goto-char (point-min))
	    (search-forward (match-string-no-properties 1))))
	 ((progn (goto-char (point-min))
		 (re-search-forward (concat "\(define-.+" (symbol-name function) " *$") nil 
t 1))
	  (message " %s" (match-string-no-properties 0)))
	 (t (goto-char (point-min)))))
    (message "%s" "No file assigned, self-made function?")))

;;;;;;

RE: Feature Request: Auto-jumping to source file (.el) upon elisperror

[Drew Adams]

> I use an adapted function `aktualisieren', which takes
> arguments as C-h f does, but then opens the source if
> available, narrowed to function mentioned. Code below.

Just bind `find-function' to a key?

Or, if you really want the code narrowed to the function definition, write a command that calls `find-function' and then narrows. 

Re: Feature Request: Auto-jumping to source file (.el) upon elisperror

[Andreas Röhler]

Am Montag, 10. Dezember 2007 20:11 schrieb Drew Adams:
> > I use an adapted function `aktualisieren', which takes
> > arguments as C-h f does, but then opens the source if
> > available, narrowed to function mentioned. Code below.
>
> Just bind `find-function' to a key?
>
> Or, if you really want the code narrowed to the function definition, write
> a command that calls `find-function' and then narrows.
>
>

You are perfectly right, thanks.

Andreas Röhler

Re: Feature Request: Auto-jumping to source file (.el) upon elisp error

[Nordlöw]

On Dec 10, 7:47 pm, Andreas Röhler <andreas.roeh...@online.de> wrote:
> Am Montag, 10. Dezember 2007 15:27 schrieb Nordlöw:
>
>
>
> > On Dec 10, 1:14 pm, Stefan Kamphausen <ska...@gmx.net> wrote:
> > > Hi,
>
> > > "Nordlöw" <per.nord...@gmail.com> writes:
> > > > But the top-most function, in your case produce-an-error(), is neither
> > > > clickable nor mentioned about its file/buffer-origin in the Debugger
> > > > output. This is sad because this is what the user/developer wants to
> > > > see first in order to most easily understand the top-most (call-stack)
> > > > context of the problem.
>
> > > you are right that the function is not clickable in the backtrace if
> > > being added interactively.  It does work however, if it was written
> > > into a separate file and then loaded via (e.g.) M-x load-file.
>
> > > Does that fit your needs?
>
> > > Regards,
> > > Stefan
> > > --
> > > Stefan Kamphausen ---http://www.skamphausen.de
> > > a blessed +42 regexp of confusion (weapon in hand)
> > > You hit. The format string crumbles and turns to dust.
>
> > Okey, thanks for your answer!
>
> > Is it still possible to make Emacs automatically open top-most source
> > code context in another window?
>
> > Thanks again,
> > Nordlöw
>
> I use an adapted function `aktualisieren', which takes
> arguments as C-h f does, but then opens the source if
> available, narrowed to function mentioned. Code below.
>
> Might that be a step forward?
>
> Andreas Röhler
>
> (defun aktualisieren (function)
>   "Go to FUNCTION (a symbol), narrow to region."
>   (interactive
>    (let ((fn (save-excursion
>                (beginning-of-defun)
>                (forward-word 2)
>                (if (featurep 'xemacs)
>                    (function-at-point)
>                  (function-called-at-point))))
>          val)
>      (list (intern-soft (completing-read (if fn
>                                              (format "Describe function (default %s): " fn)
>                                            "Describe function: ")
>                                          obarray 'fboundp t nil nil (symbol-name fn))))))
>   (if (file-readable-p
>        ;; No effect, why?
>        (condition-case nil
>            (symbol-file function)
>          (error "Keine Quelldatei gefunden")))
>       (let* ((datei (symbol-file function)))
>         (cond
>          ((file-exists-p (concat (file-name-sans-extension datei) ".el"))
>           (find-file (concat (file-name-sans-extension datei) ".el")))
>          ((file-exists-p (concat (file-name-sans-extension datei) ".el.gz"))
>           (find-file (concat (file-name-sans-extension datei) ".el.gz")))
>          ((file-exists-p (concat datei ".gz"))
>           (find-file (concat datei ".gz")))
>          (t (error (concat "Keine Quelle vorhanden"))))
>         ;; 2007-06-03 a.roeh...@web.de changed section end
>         (widen)
>         (goto-char (point-min))
>         (cond
>          ((search-forward (concat "(defun " (symbol-name function)" ") nil t) ;;
> Leerzeichen, um "-" in Funktionsnamen auszuschlie��ßen
>           (progn
>             (narrow-to-region (progn (beginning-of-defun) (point))(progn
> (end-of-defun) (point)))
>             (delete-other-windows)))
>          ((progn (goto-char (point-min))
>                  (re-search-forward (concat "(defalias '" (symbol-name
> function) " '\\([^)]+\\)") nil t 1))
>           (progn
>             (message " %s" (match-string-no-properties 1))
>             (goto-char (point-min))
>             (search-forward (match-string-no-properties 1))))
>          ((progn (goto-char (point-min))
>                  (re-search-forward (concat "\(define-.+" (symbol-name function) " *$") nil
> t 1))
>           (message " %s" (match-string-no-properties 0)))
>          (t (goto-char (point-min)))))
>     (message "%s" "No file assigned, self-made function?")))
>
> ;;;;;;

Can I make this happen automatically upon error?

Automation, automation, automation...

Thanks again,
Nordlöw