21.3: end-of-buffer resets mark

21.3: end-of-buffer resets mark

[Bjoern Milcke]

Hi,

Title:  `end-of-buffer' resets mark.
------------------------------------

Description:
------------

Do the following:

1. `set-mark-command'         (C-SPC)
2. `next-line'                (down)
3. `end-of-buffer'            (C-end, non-standard key?)
4. `exchange-point-and-mark'  (C-x C-x)

=> you will notice that the mark is at the point from where you
   called `end-of-buffer' and not the line above where you called
   `set-mark-command'.

,----[ C-h f end-of-buffer ]
| end-of-buffer is an interactive compiled Lisp function in `simple'.
| (end-of-buffer &optional ARG)
| 
| Move point to the end of the buffer; leave mark at previous position.
| With arg N, put point N/10 of the way from the end.
| 
| If the buffer is narrowed, this command uses the beginning and size
| of the accessible part of the buffer.
| 
| Don't use this command in Lisp programs!
| (goto-char (point-max)) is faster and avoids clobbering the mark.
`----

Does 'leave mark at previous position' mean set it to the current
point when calling?  If so, why is this implemented this way?  Or
how could it be done differently?

Information:
------------

Emacs: GNU Emacs 21.3.1 (i686-pc-linux-gnu, X toolkit, Xaw3d scroll
bars) of 2003-03-24
OS: Linux 2.4.19-4GB #1 Fri Sep 13 13:14:56 UTC 2002 i686 unknown

Question:
---------

Where can I look, whether bugs are already known (Issuezilla or the
like)?

-Bjoern

-- 
Bjoern Milcke                   mailto:Bjoern.Milcke@Sun.COM
Software Engineer               http://www.sun.com/staroffice
(Star|Open)Office Chart         http://graphics.openoffice.org

Re: 21.3: end-of-buffer resets mark

[Kevin Rodgers]

Bjoern Milcke wrote:

> Do the following:
> 
> 1. `set-mark-command'         (C-SPC)
> 2. `next-line'                (down)
> 3. `end-of-buffer'            (C-end, non-standard key?)
> 4. `exchange-point-and-mark'  (C-x C-x)
> 
> => you will notice that the mark is at the point from where you
>    called `end-of-buffer' and not the line above where you called
>    `set-mark-command'.


`C-u SPC C-u SPC' after or instead of `C-x C-x' will get you back to your first
mark.


> ,----[ C-h f end-of-buffer ]
> | end-of-buffer is an interactive compiled Lisp function in `simple'.
> | (end-of-buffer &optional ARG)
> | 
> | Move point to the end of the buffer; leave mark at previous position.
> | With arg N, put point N/10 of the way from the end.
> | 
> | If the buffer is narrowed, this command uses the beginning and size
> | of the accessible part of the buffer.
> | 
> | Don't use this command in Lisp programs!
> | (goto-char (point-max)) is faster and avoids clobbering the mark.
> `----
> 
> Does 'leave mark at previous position' mean set it to the current
> point when calling?  If so, why is this implemented this way?  Or
> how could it be done differently?

Yes.  Because it's convenient (to be able to return from your position
after taking a quick look at the beginning or end of the buffer).  I
don't know.


> Where can I look, whether bugs are already known (Issuezilla or the
> like)?


Use http://groups.google.com to search gnu.emacs.bug


-- 
Kevin Rodgers

Re: 21.3: end-of-buffer resets mark

[Kevin Rodgers]

Kevin Rodgers wrote:

> Bjoern Milcke wrote:
> 
>> Do the following:
>>
>> 1. `set-mark-command'         (C-SPC)
>> 2. `next-line'                (down)
>> 3. `end-of-buffer'            (C-end, non-standard key?)
>> 4. `exchange-point-and-mark'  (C-x C-x)
>>
>> => you will notice that the mark is at the point from where you
>>    called `end-of-buffer' and not the line above where you called
>>    `set-mark-command'.
> 
> `C-u SPC C-u SPC' after or instead of `C-x C-x' will get you back to 
> your first mark.

Sorry, I meant `C-u C-SPC C-u C-SPC'.

-- 
Kevin Rodgers