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From:	Junio C Hamano <gitster@pobox.com>
To:	Jeff King <peff@peff.net>
Cc:	Jakub =?utf-8?Q?Nar=C4=99bski?= <jnareb@gmail.com>,
	Stefan Beller <sbeller@google.com>,
	Linus Torvalds <torvalds@linux-foundation.org>,
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	Git Mailing List <git@vger.kernel.org>
Subject: Re: topological index field for commit objects
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Date:	Wed, 29 Jun 2016 15:11:39 -0700
In-Reply-To: <20160629220049.GA4416@sigill.intra.peff.net> (Jeff King's
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Jeff King <peff@peff.net> writes:

> Yes, though generation numbers can help with more questions (e.g., "what
> is the merge base").

Hmm, how?  I have two commits, with generation number 38 and 47,
respectively.  What generation number does the commit that is the
merge base of these two commits?

I know we can say that 38 cannot possibly be a descendant of 47, but
can we say anything else that is useful?