Runtime evaluation: Difference between revisions

=={{header|Racket}}==

Racket has the usual <tt>eval</tt> that is demonstrated [[http://rosettacode.org/wiki/Runtime_evaluation/In_an_environment#Racket here]], and in addition, it has a sandbox environment that provides a safe evaluator that is restricted from accessing files, network, etc.

<lang Racket>

#lang racket

(require racket/sandbox)

(define e (make-evaluator 'racket))

(e '(define + *))

(e '(+ 10 20))

(+ 10 20)

;; (e '(delete-file "/etc/passwd"))

;; --> delete-file: `delete' access denied for /etc/passwd

</lang>

And, of course, both of these methods can use Racket's multilingual capabilities and evaluate the code in a language with different semantics.