Re: "No further undo information" clutters *Messages* buffer

[martin rudalics]

>     Is it inevitable that `undo-more' raises an error when there is no
>     further undo information?
>
> That seems like the right thing to do.

Eventually

Undo!
undo-more: No further undo information

occupied more than 90% of my `*Messages*' buffer which made it quite
difficult to trace more interesting error messages.  I finally turned
this off by making `undo-more' display a non-logged message and ding
when there was no more undo information.  Hardly the right thing to do
but I didn't know better.

Ideally, I wanted `undo' issue `Undo...', `Redo...', etc. first.  If the
operation succeeded it would display `Undo...done', `Redo...done', etc.
Otherwise, it would issue `Undo...', `Redo...', etc. with the according
error text appended.  In any case `message_log_check_duplicate' would
take care of the rest.