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Re: Can't diff against the 00000000 revision

From
Jeff King <peff@peff.net>
Date
Jan 12, 2016, 18:20 UTC
Message-ID
<20160112182002.GA9244@sigill.intra.peff.net>
In-Reply-To
<jwvr3hmwz1n.fsf-monnier+gmane.comp.version-control.git@gnu.org>
On Tue, Jan 12, 2016 at 11:26:24AM -0500, Stefan Monnier wrote:
Show 11 quoted lines
> > And hopefully that explains why "000000" does not necessarily make a
> > good placeholder for "the empty thing". There are multiple empty things,
> > and it is not clear what:
> 
> >   git diff 0000000 1234abcd
> 
> > means. Is 0000000 a tree? A blob?
> 
> Well, Git is the one who uses 000000 to refer to an empty thing, but
> indeed it seems like it does inconsistently: it's sometimes used as the
> "empty blob" and sometimes as an "empty tree".

Yes. You can think of it kind of like a NULL pointer; it just means "nothing". So its meaning is context-dependent. The problem is if we expect to feed it back to git in a place where the context isn't obvious.

-Peff
Previous: Stefan MonnierNext: Junio C Hamano
Message 5 of 8 in “Can't diff against the 00000000 revision”
  1. Stefan MonnierJan 12, 2016
  2. Jeff KingJan 12, 2016
  3. Jeff KingJan 12, 2016
  4. Stefan MonnierJan 12, 2016
  5. Jeff KingJan 12, 2016
  6. Junio C HamanoJan 12, 2016
  7. Andreas SchwabJan 12, 2016
  8. Jeff KingJan 12, 2016

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