Re: simplifying beginning-of-defun

["Eric M. Ludlam" <eric@siege-engine.com>]

On Sun, 2009-09-27 at 12:26 +0200, Andreas Roehler wrote:
> ...
> > any argument.  So your code wouldn't be acceptable as is since it would
> > likely break several packages.
> > 
> 
> ...
> 
> 
> Hi Stefan,
> 
> reflecting this question a little bit further:
> 
> as expressive settings of `push-mark' are removed, some functions
> while rely upon and fail then.
> 
> However, `push-mark' is a very basic and considerable
> editing command. If a function needs it, it should implement it at place.
> 
> Suggest keeping things apart: move functions should
> move, not deliver a hair-cut. :)
> 
> If more is needed, another function should take over than.
> 
> All-at-once essays create complexity and never ending
> bugs finally.
> 
> So far, think simplifying is worthwhile on the longer run.
> 
> 
> Andreas

I agree with the basic mechanics of what Andreas is providing here, not
any specific feature change involved in the patch.  If there were some
function like the -raw functions he proposed that program modes would
use if they wanted exactly that behavior, and a separate interactive
function, then that opens the door for improvements on the interactive
function.

This comes up specifically with CEDET, where I can use parser
information to do a real `beginning-of-defun' for langauges whos defuns
don't happen to start with a ( in the first column.  From an interactive
point of view, a total win.  From a programs point of view, this would
mean disaster if all their code was expecting the cursor to show up on
some opening {, and not on the text actually starting the defun.

For modes like cc-mode that write their own correct
`beginning-of-defun', they would use that internally anyway, so no loss.


Right now, the feature I describe in CEDET/Semantic is done with advice
and various if statements making sure not to do the modification in
non-interactive cases.  The code is in senator.el.

http://cedet.cvs.sourceforge.net/viewvc/cedet/cedet/semantic/senator.el?view=markup

Eric