Terminology: what to call the trunk

[Matt Mackall]

On Thu, 2008-12-04 at 11:20 -0500, Greg Ward wrote:
> Let's see if I've got my history right here:
> 
>   * CVS has a formal notion of the trunk: all revisions with two
>     components (1.1, 1.2, 1.431) are on the trunk.  But it has no
>     way to *name* the trunk; in some contexts, HEAD means "tip of the
>     trunk", but that's not reliable.  And it doesn't refer to the
>     trunk as a whole, just the tip.
> 
>   * Subversion has no formal notion of the trunk, just a strong
>     convention that you do your main line of development in a 
>     directory called "/trunk".  Likewise /branches and /tags are
>     just strong conventions.  As a result, there *is* a reliable way
>     to name the trunk, but it's not universal.  If you called it 
>     "/mainline" rather than "/trunk", then that's the name you use.
> 
> So far I'm on safe ground ... I understand CVS very well and
> Subversion pretty well.  Now I'm going out on a limb:
> 
>   * Git and Mercurial both have a formal notion of the trunk and a way
>     to name it.  In git's case, it's called "master", and in
>     Mercurial's case it's called "default".  Regardless, master/default
>     is always there and can always be named: "git checkout master" and
>     "hg update default" take you back to the trunk.
> 
> Is that correct (at least as far as Mercurial is concerned)?  

If your first commit is not on the default branch, you can have a tree
with no default branch.

> Or is "default" just the *default* name of the trunk?  I.e. can I
> decide that I want to call the trunk "trunk" instead of "default"?

Sorry, no. The branch is -actually- named '' and 'default' is an alias
for that.

-- 
Mathematics is the supreme nostalgia of our time.