Demonstrates the use of Racket's custodians and namespaces to create enough isolation to "reboot" programs without restarting the whole of Racket, including possibly recompiling and reloading code.
To experiment with this:
$ racket ~/src/racket-experiments$ racket
Welcome to Racket v5.3.1.4.
-> (require "reloader.rkt")
-> (load-and-foo)
Starting worker...
test-mod: "foo"