From hadley at rice.edu  Wed May 26 17:35:54 2010
From: hadley at rice.edu (Hadley Wickham)
Date: Wed, 26 May 2010 10:35:54 -0500
Subject: [Rd] SVN vs DVCS
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>> Yes, that's a very good point (although in my experience it takes a
>> very long time to do the initial download of the SVN repository). I'm
>> not an expert on these systems, but I imagine the main downside (other
>> than speed) of having SVN upstream is that you have to keep the
>> history linear,
>
> That (non-linear history) is IMHO the biggest drawback of DVCS because that means there is no way to link a particular build to the source status and you cannot use globally valid build numbers.

Git (and I'm sure the others) provides a globally unique id for each
revision.  Isn't that sufficient?

> But feature branches are as easily (IMHO even more easily since you can closely monitor what others are contributing) worked on with SVN (routinely used with R) so I'm not sure what DVCS would buy you.

Feature branches are _much_ easier with git - to the point where some
people suggest using a separate feature branch for every feature you
develop.

> AFAICS the only benefit of DVCS is that if you are on a remote island without any internet connection you can accumulate multiple commits before merging them back. I can't say that I desperately need that functionality ;).

You have never worked on an airplane or other location without
internet access?  You must have lived a very privileged life ;)

Hadley


-- 
Assistant Professor / Dobelman Family Junior Chair
Department of Statistics / Rice University
http://had.co.nz/



[Rd] SVN vs DVCS
Hadley Wickham