Re: [PATCH] [RFD] Add repoid identifier to commit [its a workspace id, isn't it?]

From: Jon Seymour <jon.seymour@gmail.com>
Date: May 13, 2005, 23:49 UTC
Message-ID: <2cfc403205051316495b46115e@mail.gmail.com>
In-Reply-To: <20050513222502.GD32232@pasky.ji.cz>

On 5/14/05, Petr Baudis <pasky@ucw.cz> wrote:

Show 16 quoted lines

> Dear diary, on Fri, May 13, 2005 at 03:37:47AM CEST, I got a letter
> where Jon Seymour <jon.seymour@gmail.com> told me that...
> > >
> > > I would like to suggest a few limiters are set on the repoid.  In
> > > particular, I'd like to suggest that a repoid is a UUID, that a file is
> > > used to track it (.git/repoid), and that if it doesn't exist, a new one
> > > is created from /dev/urandom.
> > >
> >
> > I think I understand what Thomas is trying to achieve, but I think
> > there is a naming problem here. The marker really isn't a repoid - it
> > is a workspace id.
> 
> Why not just call the thing "branch"? It's as well eligible for that
> term as anything. :-)
>

I very nearly agreed with you except for one thing. In a traditional SCM, a branch is something that can be contributed by multiple people but I don't think we want that meaning here.

Consider this graph where there is a main Trunk R, and a branch B and two programmers Ba and Bb working on a branch B. Thomas wants to be able to form views of the merge order of 3 workspaces (W(R), W(Ba) and W(Bb)), even though Ba and Bb are working on the same "branch" in SCM terms.

Rn -------------
|      \         \ 
Rn-1 Ba,n   Bb,n
|     /             |
Rn-2             |
|       \           |
Rn-3 Ba,n-1  |
|    /             /
Rn-4 -----------

Also, most times in a traditional SCM, branches diverge, but the behaviour we are interested in here is the repeated converging and diverging of workspaces on the same "branch" [ I know, a branches can be used in that way in traditional SCMs, but that is a degenerate case of their intended use - maintaining paths of long term divergence ].

So, while I think there may well be some value is a separate "branchid" attribute in a commit, I think they are describing (slightly) different things.

jon

-- 
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