Re: git branch --switch?

[Rene Herman <rene.herman@gmail.com>]

On 04/17/2007 04:31 PM, Brian Gernhardt wrote:

>> Is it possible to switch the current branch without checking it out? 
>> Not really essential, but I'm happily flaundering around with git and 
>> still start from scratch fairly regularly; to speed this up I've found 
>> the -n switch to git clone useful and would like something similar 
>> when reconstructing my "branch hierarchies".
>>
>> Upto now I only know about "git checkout" (with or without -b) to 
>> switch the current branch. As said it's not really essential, but I 
>> was expecting there would be something like a "branch --switch". Did I 
>> overlook it?
> 
> Perusing git-checkout points me to git-symbolic-ref to update the HEAD 
> ref to a new branch:
> 
> git symbolic-ref HEAD refs/heads/<branch>
> 
> However, I'm somewhat confused as to why you'd want HEAD and the working 
> directory to get out of sync.

Thank you for the answer. Well, as said, it's not essential, but I was just 
now rebuilding a repo and have a few branches that I all want to be based on 
the same revision. Say, branch a, b and c, based on v2.6.20.

git clone -l -s -n <a local linux repo> local
git checkout -b v20 v2.6.20
git branch a
git branch b
git branch c

Step 1, 3, 4 and 5 of this are nearly instantaneous but 2 isn't -- this repo 
sits on a P1 with 64M of memory and a disk doing 8 M/s which is probably the 
only reason I thought asking about it was a good idea in the first place...

You'd be quite right in saying that there isn't much point; if I want to now 
start populating branch a, I have to "git checkout a" anyway, and that 
action _will_ now be instantaneous. If I'd replaced 2 with:

git branch --create-and-set-as-current v20 v2.6.20

then I will not have won any time until that 6th "git checkout a" step.

The checkout of v20 was superfluous in this though, and I just expected I 
should be able to skip that. It fitted my mental model...

Rene.