help-go-back

help-go-back

[Karl Chen]

`Help-go-back' hasn't been working.  Here are two possible fixes.

I think `help-go-back' was kludgey before (that's why it broke) so
patch #2 is better.

It would also be nice if there were a `help-go-forward' (opposite
of `help-go-back').  I can write this if there is interest.


--- /home/quarl/local/Node-Linux-i686/stow/emacs-cvs/share/emacs/21.3.50/lisp/help-mode.el	Sat May  8 13:24:44 2004
+++ /tmp/buffer-content-33160vh	Sat May  8 13:24:58 2004
@@ -579,7 +579,7 @@
 (defun help-go-back ()
   "Invoke the [back] button (if any) in the Help mode buffer."
   (interactive)
-  (let ((back-button (button-at (1- (point-max)))))
+  (let ((back-button (button-at (- (point-max) 2))))
     (if back-button
 	(button-activate back-button)
       (error "No [back] button"))))


--- /home/quarl/local/Node-Linux-i686/stow/emacs-cvs/share/emacs/21.3.50/lisp/.backup/help-mode.el.~1~	Thu Apr 29 11:43:32 2004
+++ /home/quarl/local/Node-Linux-i686/stow/emacs-cvs/share/emacs/21.3.50/lisp/help-mode.el	Sat May  8 13:35:05 2004
@@ -577,12 +577,11 @@
 	(goto-char position)))))
 
 (defun help-go-back ()
-  "Invoke the [back] button (if any) in the Help mode buffer."
+  "Go back to previous help buffer."
   (interactive)
-  (let ((back-button (button-at (1- (point-max)))))
-    (if back-button
-	(button-activate back-button)
-      (error "No [back] button"))))
+  (if help-xref-stack
+      (help-xref-go-back (current-buffer))
+    (error "No previous help buffer.")))
 
 (defun help-do-xref (pos function args)
   "Call the help cross-reference function FUNCTION with args ARGS.



-- 
Karl 2004-05-08 13:26

Re: help-go-back

[Juri Linkov]

Karl Chen <quarl@hkn.eecs.berkeley.edu> writes:
> `Help-go-back' hasn't been working.  Here are two possible fixes.
>
> I think `help-go-back' was kludgey before (that's why it broke) so
> patch #2 is better.

I think the second patch is better, because it doesn't rely on
the location of the [back] button.

> It would also be nice if there were a `help-go-forward' (opposite
> of `help-go-back').  I can write this if there is interest.

It is not possible to implement it with the current `help-xref-stack'
variable.  A new variable could be added that will record the full
Help history.  And it might be as useful as full history of Info nodes
where an additional variable with full history was added recently.

-- 
Juri Linkov
http://www.jurta.org/emacs/

Re: help-go-back

[Karl Chen]

>>>>> "Juri" == Juri Linkov <juri@jurta.org> writes:
    >> It would also be nice if there were a `help-go-forward'
    >> (opposite of `help-go-back').  I can write this if there is
    >> interest.
    Juri> 
    Juri> It is not possible to implement it with the current
    Juri> `help-xref-stack' variable.  A new variable could be
    Juri> added that will record the full Help history.  And it
    Juri> might be as useful as full history of Info nodes where
    Juri> an additional variable with full history was added
    Juri> recently.

I was thinking a list of nodes to go forward to (reverse of the
'back' stack).  I'm not sure what you mean re. Info nodes, do you
want to combine the two histories?

-- 
Karl 2004-05-08 15:21

Re: help-go-back

[Juri Linkov]

Karl Chen <quarl+dated+1084486903.a9a7a9@nospam.quarl.org> writes:
>>>>>> "Juri" == Juri Linkov <juri@jurta.org> writes:
>     >> It would also be nice if there were a `help-go-forward'
>     >> (opposite of `help-go-back').  I can write this if there is
>     >> interest.
>     Juri> It is not possible to implement it with the current
>     Juri> `help-xref-stack' variable.  A new variable could be
>     Juri> added that will record the full Help history.  And it
>     Juri> might be as useful as full history of Info nodes where
>     Juri> an additional variable with full history was added
>     Juri> recently.
>
> I was thinking a list of nodes to go forward to (reverse of the
> 'back' stack).  I'm not sure what you mean re. Info nodes, do you
> want to combine the two histories?

No, I meant not to combine, but to implement the full Help history list
similar to full Info history list recently implemented, i.e. a list
of all visited Help elements which is displayed in the Help buffer by
a special command, and where older help elements could be revisited by
selecting an element from the full history list.

However, AFAIU, you propose a stack of forward elements, which is
filled by `help-xref-go-back', used by a new `help-xref-go-forward'
command and cleared after the first visit of some other cross-reference.
This may be useful as well, although generally this is a subset of
the full history list.

BTW, since you misunderstood me in such a way that I proposed to
combine the Info and Help histories, it seems it was not accidentally,
because more close integration of Help with Info seems very natural.
Many improvements could be done here.  At least, the Help buffer could
provide automatic buttons with links to Info manuals and call
something like `info-lookup-symbol' or `Info-goto-emacs-command-node'.

-- 
Juri Linkov
http://www.jurta.org/emacs/

Re: help-go-back

[Nick Roberts]

 > Many improvements could be done here.  At least, the Help buffer could
 > provide automatic buttons with links to Info manuals and call
 > something like `info-lookup-symbol' or `Info-goto-emacs-command-node'.

It already does. Do `C-h f' on vc-directory, for example.

Nick

Re: help-go-back

[Juri Linkov]

Nick Roberts <nick@nick.uklinux.net> writes:
>  > Many improvements could be done here.  At least, the Help buffer could
>  > provide automatic buttons with links to Info manuals and call
>  > something like `info-lookup-symbol' or `Info-goto-emacs-command-node'.
>
> It already does. Do `C-h f' on vc-directory , for example.

Yes, it does, but only for a few functions where the text
"See Info node ..." was added manually.

What I proposed is to add this text automatically in the Help buffer
for every function described in Info manuals.

-- 
Juri Linkov
http://www.jurta.org/emacs/

Re: help-go-back

[Eli Zaretskii]

> From: Juri Linkov <juri@jurta.org>
> Date: Sun, 09 May 2004 04:11:29 +0300
> 
> Yes, it does, but only for a few functions where the text
> "See Info node ..." was added manually.
> 
> What I proposed is to add this text automatically in the Help buffer
> for every function described in Info manuals.

You mean, you want Help to scan the Info manuals before it describes
the Help buffer?  (How else will it know that a function is documented
in some manual?)  Won't this make Help too slow?

Re: help-go-back

[Juri Linkov]

Eli Zaretskii <eliz@gnu.org> writes:
>> From: Juri Linkov <juri@jurta.org>
>> Date: Sun, 09 May 2004 04:11:29 +0300
>> 
>> Yes, it does, but only for a few functions where the text
>> "See Info node ..." was added manually.
>> 
>> What I proposed is to add this text automatically in the Help buffer
>> for every function described in Info manuals.
>
> You mean, you want Help to scan the Info manuals before it describes
> the Help buffer?  (How else will it know that a function is documented
> in some manual?)  Won't this make Help too slow?

It can be optimized by caching Info indexes in Lisp structures.

-- 
Juri Linkov
http://www.jurta.org/emacs/

Re: help-go-back

[Richard Stallman]

    No, I meant not to combine, but to implement the full Help history list
    similar to full Info history list recently implemented, i.e. a list
    of all visited Help elements which is displayed in the Help buffer by
    a special command, and where older help elements could be revisited by
    selecting an element from the full history list.

We don't really need this feature, and based on my experience making
changes in that code, adding this is very likely to be break things.
So let's stop thinking about it.

Re: help-go-back

[Stefan Monnier]

> `Help-go-back' hasn't been working.  Here are two possible fixes.

Thank you.  I've installed your second fix.


        Stefan