Re: [BUG] Highly inconsistent diff UI

> The first thing to do is to eradicate "diff A..B" from the
> documentation, and a dozen or more lines in your complaint will go
> away with that single change.
>
> As you know, diff is about two endpoints, and A..B is not a way to
> specify two endpoints, and not erroring it out whenever we see a
> negative revision is a mere courtesy to old timers who knew the
> command line parser was shared with rev-list machinery.
>
> There is no reason to forbid the syntax, but encouraging its use is
> counterproductive and will lead to confusions to new people as you
> pointed out.

> The only issue is to come up with a concise alternative way to
> express "diff A...B", perhaps "diff --compare-with-base A B", and
> then you can choose not to say anything but an object name (and no
> range notation) on the command line (if you do not "diff A...B", it
> can already be done by not using "diff A..B").