[racket] Limiting net-repl provided functions

>
> The sandbox is working in an isolated world (by design, of course), so
> you need to do the (require "sb-functions.rkt") inside the sandbox.
> For example, just use (sb-eval '(require ...)).
>
> --
>           ((lambda (x) (x x)) (lambda (x) (x x)))          Eli Barzilay:
>                     http://barzilay.org/                   Maze is Life!

Wouldn't that mean that the sb-evaluator has to be first initiated to
understand 'require' plus many other primitives, not just the intented f1,
f2, f3? Is this even possible?

br, jukka