[racket] collection installer that does raco link

If I want to have a PLaneT package "foo" that sets up a "#lang foo" to 
refer to itself, is the following the right way to do the "raco link"?

* Have the "info.rkt" "post-install-collection" use procedure "links" 
from module "setup/link", using "this-expression-source-directory" to 
figure out the right install-time path.

(BTW, I considered additionally setting "info.rkt" "can-be-loaded-with" 
to "'none", since, unlike reusable libraries, only one version of this 
language is needed per Racket installation.  But I'm thinking that 
setting "can-be-loaded-with" to "'all", and having a 
last-installed-version-wins-the-raco-link policy, would make version 
updates more resilient.  However, if the package someday also provides a 
DrRacket extension, multiple versions could be a problem for that, IIRC.)

Neil V.