===== Description =====
We would like to be able to extract only src/sys or ports/french out of the repository for efficiency and disk space reasons.

===== Current Implementation =====

===== SVN Implementation =====
Trivial.  You can directly check out any part of the tree that you want by simply specifying the path name.  It works the same as CVS.

===== Hg Implementation =====
This is an often mentioned feature which is not implemented yet.  You can workaround this limitation for the working directory in Hg but not for the repository itself (.hg/*).  The other way to do that is to have a collection of repositories linked together through the "hgforest" or the "overlay" extensions.

===== Git Implementation =====
Git has recently gotten preliminary support for submodules which are linked repositories within a super-repository. This functionality may be too heavy weight for partial clones though, in which case a simple daemon could be implemented that checks out only a single tree object from a repository without history.

===== Monotone Implementation =====