bug#24804: 25.1; posn-at-point erroneously signals an error

[Eli Zaretskii]

> From: Andreas Politz <politza@hochschule-trier.de>
> Cc: rudalics@gmx.at,  24804@debbugs.gnu.org
> Date: Sat, 29 Oct 2016 16:26:47 +0200
> 
> Eli Zaretskii <eliz@gnu.org> writes:
> 
> > Andreas, can you try the patch below?  Thanks.
> 
> I can confirm, that the error regarding above recpie goes away.

Great, I will push it to master soon.

> Though I'm pretty confused about what this function should actually
> return in this case.  E.g. in the scenario above, evaluating (posn-x-y
> (posn-at-point x)) with x=point-min, resp. x=point-max, returns (0 . 0),
> resp.  (747 . 0), where 747 is the width of the image.  Does that sound
> right ?

It sounds right to me: the first position is at the image, the second
is after the image, so its X coordinate should be the image width.
Does that make sense?