>>>>> "Manuel" == Manuel Serrano <Manuel.Serrano(a)sophia.inria.fr&gt; writes: Manuel> The strings "->" and "<-" are still on the screen. Is this Manuel> really normal? For your information, XEmacs 21.4 removes Manuel> the strings. In XEmacs the overlay API is implemented using the extent primitives, and by default new extents are "detachable": ------------------------------------------------------------------------ Detached Extents ================ A detached extent is an extent that is not attached to a buffer or string but can be re-inserted. Detached extents have a start position and end position of `nil'. Extents can be explicitly detached using `detach-extent'. An extent is also detached when all of its characters are all killed by a deletion, if its `detachable' property is set; if this property is not set, the extent becomes a zero-length extent. ------------------------------------------------------------------------ See also C-h f set-extent-property RET. So if you set the detachable property to nil, you should get the same behavior as in Emacs. Depending on how you manipulate those extents you may prefer to do (when (featurep 'xemacs) (set-extent-property ov 'detachable nil)) at creation rather than checking for xemacs at deletion time. This seems to expose a bug in XEmacs's overlay handling (for zero-length overlays), but it's irrelevant if you're just going to go ahead and delete it anyway. HTH

> I don't know what happens in XEmacs--I only work on Emacs. > > The code you sent creates overlays. They would continue to exist and > be displayed until something removes them with delete-overlay. There > seems to be code in flyspell.el that tries to delete them, so the > question is why it does not delete these overlays. > > Manuel, could you debug it? I still think the problem is in Emacs or in the documentation about overlay. In the section "Overlays properties" it is said: -----|-----|-----|-----|-----|-----|-----|-----|-----|-----|-----|-----|----- `before-string' This property's value is a string to add to the display at the beginning of the overlay. The string does not appear in the buffer in any sense--only on the screen. `after-string' This property's value is a string to add to the display at the end of the overlay. The string does not appear in the buffer in any sense--only on the screen. -----|-----|-----|-----|-----|-----|-----|-----|-----|-----|-----|-----|----- So, I would have guessed that when a region using an overlay with a before-string and an after-string properties is deleted, the before-string and after-string disappear of the screen. That is, I have tried: -----|-----|-----|-----|-----|-----|-----|-----|-----|-----|-----|-----|----- (require 'flyspell) (defvar ov nil) (defun add-ov (beg end) (setq ov (make-overlay beg end nil t nil)) (overlay-put ov 'face 'flyspell-incorrect-face) (overlay-put ov 'mouse-face 'highlight) (overlay-put ov 'before-string "->") (overlay-put ov 'after-string "<-")) (defun del-ov () (delete-overlay ov)) -----|-----|-----|-----|-----|-----|-----|-----|-----|-----|-----|-----|----- Then, on a random buffer: -----|-----|-----|-----|-----|-----|-----|-----|-----|-----|-----|-----|----- (add-ov 1 4) (delete-region 1 4) -----|-----|-----|-----|-----|-----|-----|-----|-----|-----|-----|-----|----- The strings "->" and "<-" are still on the screen. Is this really normal?

Check out the `evaporate' property of overlays. You could set it to t so that your overlays get automatically deleted when their size gets down to 0.