Re: before- and after-string issues

[martin rudalics]

> This scenario is not fully specified.  Please specify, for each
> overlay, whether its beginning marker advances and whether its end
> marker advances.  If you describe a fully-specified scenario,
> I presume I can follow it.

(let ((B (make-overlay (point) (1+ (point))))
      (A (make-overlay (point) (1+ (point)))))
  (overlay-put B 'before-string "B")
  (overlay-put A 'after-string "A"))

should get you two overlays covering one character with "B" appearing
before and "A" after the character.  Deleting that character will cause
the overlays to change places resulting in something like "AB".