From mboxrd@z Thu Jan  1 00:00:00 1970
From: Linus Torvalds <torvalds@osdl.org>
Subject: Re: A note on merging conflicts..
Date: Fri, 30 Jun 2006 20:59:54 -0700 (PDT)
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On Fri, 30 Jun 2006, Linus Torvalds wrote:
>
> (it's not strictly a valid set operation, but it approaches being an 
> "xor" instead of a union or an intersection or a difference).

Oh, I guess it _is_ perfectly valid. It's called a "symmetric difference" 
in set theory.

So from a set standpoint:

	Git op:			Set theory:

	git-rev-list a..b	// difference: B - A
	git-rev-list b..a	// difference: A - B

	git-rev-list a b	// union of A B (order doesn't matter)

	git-rev-list a...b	// symmetric difference A B (order doesn't matter)

	git-rev-list $(git-merge-base --all a b)
				// intersection of A and B

I think.

		Linus