bug#59996: 30.0.50; Overlays section of Elisp manual still states that overlays scale linearly

[Eli Zaretskii]

> From: Ihor Radchenko <yantar92@posteo.net>
> Cc: 59996-done@debbugs.gnu.org
> Date: Tue, 13 Dec 2022 10:42:17 +0000
> 
> Eli Zaretskii <eliz@gnu.org> writes:
> 
> > I guess that entire section should be audited for inaccuracies now;
> > reviews and patches are welcome.
> 
> Another part that requires update:
> 
> 
>        Emacs stores the overlays of each buffer in two lists, divided around
>     an arbitrary center position.  One list extends backwards through the
>     buffer from that center position, and the other extends forwards from
>     that center position.  The center position can be anywhere in the
>     buffer.
>     
>      -- Function: overlay-recenter pos
>          This function recenters the overlays of the current buffer around
>          position POS.  That makes overlay lookup faster for positions near
>          POS, but slower for positions far away from POS.
>     
>        A loop that scans the buffer forwards, creating overlays, can run
>     faster if you do ‘(overlay-recenter (point-max))’ first.
> 
>     
> ‘after-string’/‘before-string’ property description might mention that
> string are not displayed if the end/beginning of the overlay is not
> displayed for some reason.
> 
> Also, it might be worth highlighting that unlike text properties,
> overlays advance regardless whether insert or insert-and-inherit is used
> to insert the buffer text.

Fixed, thanks.