We are considering a move from SVN to Mercurial, and have encountered a stumbling block.
We currently use svn:externals to automatically pull a common s
svn:externals
It appears that the functionality of the Forest Extension is being implemented into core Mercurial (as of 1.3):
https://www.mercurial-scm.org/wiki/Subrepository.
Currently marked as "experimental" but perhaps will be the route to handle svn:external -type functionality as of v1.4.