VCS comparison table

[Jakub Narebski]

Linus Torvalds wrote:
>>> About "checkouts", i.e. working directories with repository elsewhere:
>>> you can use GIT_DIR environmental variable or "git --git-dir" option,
>>> or symlinks, and if Nguyen Thai Ngoc D proposal to have .gitdir/.git
>>> "symref"-like file to point to repository passes, we can use that.
>> 
>> It sounds like the .gitdir/.git proposal would give Git "checkouts", by
>> our meaning of the term.
> 
> Well, in the git world, it's really just one shared repository that has 
> separate branch-namespaces, and separate working trees (aka "checkouts"). 
> So yes, it probably matches what bazaar would call a checkout.
> 
> Almost nobody seems to actually use it that way in git - it's mostly more 
> efficient to just have five different branches in the same working tree, 
> and switch between them. When you switch between branches in git, git only 
> rewrites the part of your working tree that actually changed, so switching 
> is extremely efficient even with a large repo. 

Unless you have branch(es) with totally different contents, like git.git
'todo' branch.

> So there is seldom any real need or reason to actually have multiple 
> checkouts. But it certainly _works_.

But without .git being either symlink, or .git/.gitdir "symref"-link,
you have to remember what to ser GIT_DIR to, or parameter for --git-dir
option.

I'd like to mention once again that in Git branches and tags have
totally separate namespace than repository namespace.
-- 
Jakub Narebski
Poland