Re: confusing info in C-u C-x =

[Juri Linkov <juri@jurta.org>]

> I've just installed two changes to fix it.
>
> (1) Use *Help-2* buffer if the current buffer is *Help*.
> The function describe-text-properties already does it.

*Help-2* is not handled correctly when same-window-regexps
contains the standard regexp to handle buffers with similar names:
"\\*Help\\*\\(\\|<[0-9]+>\\)".

I propose using (generate-new-buffer-name "*Help*") in both functions
to generate the standard unique names like *Help*<2>.

Also the *Help* buffer created by `describe-char' misses "[back]"
button.  It is too bad because it loses the stack of visited
Help items.  The patch below adds "[back]" button without putting
the `describe-char' item to the help stack, because there is no
reliable way to recreate the Help buffer for `describe-char'.
Its argument is `pos', but this position and buffer may not exist
when the Help buffer for `describe-char' is recreated later after
returning from its next Help item's buffer.

There is one problem with having "[back]" button in describe-text-mode.
TAB can't navigate to it.  But this is minor disadvantage because
RET still works on it.

Index: lisp/descr-text.el
===================================================================
RCS file: /cvsroot/emacs/emacs/lisp/descr-text.el,v
retrieving revision 1.43
diff -c -r1.43 descr-text.el
*** lisp/descr-text.el	8 Dec 2005 01:38:50 -0000	1.43
--- lisp/descr-text.el	9 Dec 2005 09:55:57 -0000
***************
*** 160,166 ****
        (let ((buffer (current-buffer))
  	    (target-buffer "*Help*"))
  	(when (eq buffer (get-buffer target-buffer))
! 	  (setq target-buffer "*Help-2*"))
  	(save-excursion
  	  (with-output-to-temp-buffer target-buffer
  	    (set-buffer standard-output)
--- 160,166 ----
        (let ((buffer (current-buffer))
  	    (target-buffer "*Help*"))
  	(when (eq buffer (get-buffer target-buffer))
! 	  (setq target-buffer (generate-new-buffer-name "*Help*")))
  	(save-excursion
  	  (with-output-to-temp-buffer target-buffer
  	    (set-buffer standard-output)
***************
*** 466,472 ****
  				(char-to-string char)))))
  	 (orig-buf (current-buffer))
  	 (help-buf (if (eq orig-buf (get-buffer "*Help*"))
! 		       "*Help-2*" "*Help*"))
  	 item-list max-width unicode)
  
      (if (or (< char 256)
--- 466,473 ----
  				(char-to-string char)))))
  	 (orig-buf (current-buffer))
  	 (help-buf (if (eq orig-buf (get-buffer "*Help*"))
! 		       (generate-new-buffer-name "*Help*")
! 		     "*Help*"))
  	 item-list max-width unicode)
  
      (if (or (< char 256)
***************
*** 621,626 ****
--- 622,629 ----
  					 item-list)))
      (with-output-to-temp-buffer help-buf
        (with-current-buffer standard-output
+ 	(let ((help-xref-following t))
+ 	  (help-setup-xref nil nil))
  	(set-buffer-multibyte multibyte-p)
  	(let ((formatter (format "%%%ds:" max-width)))
  	  (dolist (elt item-list)
***************
*** 725,731 ****
  	(save-excursion
  	  (set-buffer orig-buf)
  	  (describe-text-properties pos help-buf))
! 	(describe-text-mode)))))
  
  (defalias 'describe-char-after 'describe-char)
  (make-obsolete 'describe-char-after 'describe-char "22.1")
--- 728,737 ----
  	(save-excursion
  	  (set-buffer orig-buf)
  	  (describe-text-properties pos help-buf))
! 	(describe-text-mode)
! 	(toggle-read-only 1)
! 	(help-make-xrefs (current-buffer))
! 	(print-help-return-message)))))
  
  (defalias 'describe-char-after 'describe-char)
  (make-obsolete 'describe-char-after 'describe-char "22.1")

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