"Or, if using Arc libraries from your Racket program is more trouble than it's worth right now (and I imagine it could be), perhaps you'd like to implement a REPL with Racket's web server. Of course the Arc forum probably isn't the best place to ask about that, the Racket email lists would probably be more help, but I imagine it's probably possible since Racket does have eval."
It's actually kind of an example in (the most advanced part of) the Racket getting started pages:
> Given the "many" example, it’s a small step to a web server that accepts arbitrary Racket code to execute on the server. In that case, there are many additional security issues besides limiting processor time and memory consumption. The racket/sandbox library provides support to managing all those other issues. (http://docs.racket-lang.org/more/index.html)
The racket/sandbox module reference has another example:
These examples complement each other. The first doesn't actually 'eval any client input, and the second uses a TCP socket directly rather than bothering with session handling or HTTP, but each of them picks up the other's slack. I'm a bit surprised there aren't many Racket Web REPLs for Racket the way there are for Arc.
