bug#14518: C and Emacs Lisp code parts

[Eli Zaretskii]

> From: Andreas Röhler <andreas.roehler@easy-emacs.de>
> Cc: Eli Zaretskii <eliz@gnu.org>, John Wiegley <johnw@gnu.org>
> Date: Thu, 7 Jul 2016 09:33:12 +0200
> 
> IMHO in the case given the reasons are pretty simple. See for example in
> 
> 'prepare-abbrev-list-buffer':
> ...
>       (dolist (table abbrev-table-name-list)
> 
> Such happens not only there. With the number of active modes/tables it 
> growths - maybe exponentially?
> 
> Also: why define-abbrevs must process the whole buffer? Why not deal with 
> just the changed parts?

(This is no longer about C vs Lisp, right?)

If you want to propose changes in abbrevs.el whose purpose is to speed
it up, please do.  But please also include with the changes the
rationale in the form of timing measurements, so that, if the code
becomes more complicated as result, we could judge the speed-up
against the added complexity.

Thanks.