Re: should search ring contain duplicates?

[Richard Stallman]

    > More precisely, it does not preserve the old head.
    > Instead it deletes that and then adds a new element.
    > But the result is, all the same, to have just one, not two.
    > This is all that matters, as far as I can see.

    It depends on the setting of history-delete-duplicates, whereas
    the code in read-from-minibuffer does not.

Ok, now I see the issue.

    The following version of add-to-history which obeys the same rules
    as read-from-minibuffer, including the keep-all arg.

Thanks, and please install it.
Please update the Lisp Manual and etc/NEWS, too.

Thanks.