Re: RefTree: Alternate ref backend

From: Martin Fick <mfick@codeaurora.org>
Date: Dec 22, 2015, 20:56 UTC
Message-ID: <6263203.WlZuyGWxlh@mfick1-lnx>
In-Reply-To: <4689734.cEcQ2vR0aQ@mfick1-lnx>

On Tuesday, December 22, 2015 06:17:28 PM you wrote:

> On Tue, Dec 22, 2015 at 7:41 AM, Michael Haggerty

<mhagger@alum.mit.edu> wrote:

Show 14 quoted lines

>
> At a deeper level, the "refs/" part of reference names is
> actually pretty useless in general. I suppose it
> originated in the practice of storing loose references
> under "refs/" to keep them separate from other metadata
> in $GIT_DIR. But really, aside from slightly helping
> disambiguate references from paths in the command line,
> what is it good for? Would we really be worse off if
> references' full names were
>
>     HEAD
>     heads/master
>     tags/v1.0.0
>     remotes/origin/master (or remotes/origin/heads/master)

I think this is a bit off, because

  HEAD != refs/HEAD

so not quite useless.

But, I agree that the whole refs notation has always bugged me, it is quirky. It makes it hard to disambiguate when something is meant to be absolute or not. What if we added a leading slash for absolute references? Then I could do something like:

/HEAD /refs/heads/master /refs/tags/v1.0.0 /refs/remotes/origin/master

I don't like that plumbing has to do a dance to guess at expansions, how many tools get it wrong (do it in different orders, miss some expansions...). With an absolute notation, plumbing could be built to require absolute notations, giving more predictable interpretations when called from tools.

This is a long term idea, but it might make sense to consider it now just for the sake of storing refs, it would eliminate the need for the ".." notation for "refs/..HEAD".

Now if we could only figure out a way to tell plumbing that something is a SHA, not a ref? :)

-Martin

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