[wishlist] git-archive -L

Hi Rene,

I wanted to do that myself, but I sadly miss the time right now, so I wonder if you'd know how to do the following.

We have in our repository a kind of modular system (for a family of web sites) where each web-site uses a (versionned) symlink farm. IOW it works basically that way:

    www/module1
    www/module2
    product_A/www/module1 -> ../../www/module1
    product_A/www/module_A
    product_B/www/module1 -> ../../www/module1
    product_B/www/module2 -> ../../www/module2
    product_B/www/module_B

Though product_A and _B even if they share a fair amount of code, are separate products and when we release, we'd like to be able to perform from inside:

    git archive --format=tar -L product_$A

where -L basically does what it does in cp: dereference symlinks. To make the thing hairier, we also have symlinks _inside_ www/ (pointing into the same subtree) that we'd like to keep if possible (even if it's not a big deal).

So I'd suggest something where -L only dereferences the symlink if it goes outside of the list of paths passed to git-archive, and -LL (or -L -L) dereferences anything. Of course this would only make sense if the symlinks resolve to something that is tracked :)

For now we git archive the whole repository, use tar xh; rm what we don't like, reset the symlinks we want to keep, and retar, which is kind of counterproductive :)