50 minutes ago, Robby Findler wrote:
>
> I'm not sure either (this is certainly not the only contract that's
> checked during the execution of PLAI programs, but maybe it's the
> only provide/contract one?), but once I disabled that, my sample
> solution for the next exercise went through.
>
> It would be good to know how to get a better short-term solution,
> however (like making a more relaxed sandbox that allows exists
> queries in the handin server).
This is "easy":
(parameterize ([sandbox-path-permissions '([exists "/"])])
...make the evaluator...)
except that I think that in the context of the handin server you don't
create it directly. It's probably doable by making the change
globally, via a hook:
Create a "hook.rkt" file with:
#lang racket/base
(provide hook)
(require racket/sandbox)
(define (hook what session alist)
(when (eq? what 'server-start)
(sandbox-path-permissions '([exists "/"]))))
Then wire it in with an entry in the config file that says:
(hook-file "hook.rkt")
Or, if you already have a hook, then add the parameter change to it.
--
((lambda (x) (x x)) (lambda (x) (x x))) Eli Barzilay:
http://barzilay.org/ Maze is Life!
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