Re: "Buttons" in a message buffer that evaluate to plain text?

Tim Landscheidt <[email protected]> writes:

> One minor flaw: Replacing the button's "label" (i. e., the
> text "[ ENTHALTUNG ]", etc.) will move point to either the
> beginning or the end of the replaced text.  Aside from
> replace-region-contents I also tried delete-char/insert with
> overwrite-mode set to 'overwrite-mode-textual, but the
> latter does not seem to have any effect to turn insert into
> a "replace".
>
> While I probably could do some arithmetics with point or
> mark myself

That's what I do (for point, I don't handle the mark).

> any (in my case hypothetical) marker would still be moved.
>
> How can I actually replace the character/text at point
> without deleting and inserting?

I dunno - maybe none?  `replace-region-contents' has been improved
recently, see bug#76313 for the discussion.  I have not investigated,
but I guess this question has been thought about.  If you are
interested, you could have a look at what other kinds of button
implementations do - the customize buttons and widgets for example.

Side note: there is the nontrivial case of point's old position being
outside the button when the new text is smaller than the replaced text.


Michael.