Re: git fsck: unreachable vs. dangling

From: Sebastian Schuberth <sschuberth@gmail.com>
Date: Apr 14, 2015, 08:58 UTC
Message-ID: <CAHGBnuPepR11r9qpxb2G7pGhq0iiaqCCLnbt5NB_xohHi=cVxA@mail.gmail.com>
In-Reply-To: <552CD4C8.2020700@drmicha.warpmail.net>

On Tue, Apr 14, 2015 at 10:50 AM, Michael J Gruber <git@drmicha.warpmail.net> wrote:

Show 9 quoted lines

> "to dangle" means "to hang loosely".
>
> So, in the description above, "A^ dangles from A loosely" because it
> hangs from A (you can reach it from A) but loosely, because it would
> "drop" if A gets dropped and A is "likely" to be dropped (because it is
> unreachable by refs). But A^ is not dangling in our terminology.
>
> If you *reverse the arrows*, i.e. consider A^ pointing to A, it becomes
> more apparent that A is dangling: it is an unreferenced leaf node.

That's exactly what confused me. In the very literal sense, something can only "hang loosely", i.e. dangle, if it's only tied at *one* end, and that's the case for A (which is only connected to A^) but not for A^ (which is connected to its parent, and A). Especially when talking about A as a "leaf" node, like in the leaf of a natural tree, I would think that A is dangling.

-- 
Sebastian Schuberth