source $stdenv/setup
tagtext=""
tagflags=""
if test -n "$tag"; then
tagtext="(tag $tag) "
tagflags="--tag=$tag"
fi
header "getting $url $partial ${tagtext} into $out"
darcs get --no-pristine-tree $partial $tagflags "$url" "$out"
# remove metadata, because it can change
rm -rf "$out/_darcs"
stopNest