From mboxrd@z Thu Jan  1 00:00:00 1970
From: Jakub Narebski <jnareb@gmail.com>
Subject: Re: [RFD] Git glossary: 'branch' and 'head' description
Date: Sun, 21 May 2006 10:30:23 +0200
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David K=E5gedal wrote:

> Jakub Narebski <jnareb@gmail.com> writes:
[...]
>> So from the user's point of view, 'branch' is simply _named line of
>> development_. Refer to topic and tracking branches.
>=20
> But the definition of 'branch' in git is quite different from the
> definition in CVS or many other systems.  It CVS, each revision
> (commit) belongs to a branch, and the branch is a linear sequence of
> revisions, not a full DAG.  In git, a commit doesn't really "belong"
> in any specific branch.
>=20
> So, while it makes sense to describe branches as "lines of
> development" in general terms, it is also important to note the
> specific meaning of 'branch' in the context of git; i.e. as the
> history of a single head commit.

We can always say that branch is 1-st parent linear history of head bra=
nch,
up to unmarked but computable branching/fork/creation point, i.e.

  {i =3D 0..N: branch-head~i}

where N is the length of the branch.

BTW. HEAD~0 =3D=3D HEAD, isn't it?

--=20
Jakub Narebski
Warsaw, Poland