In einer eMail vom 16.02.00 14:05:52 (MEZ) Mitteleurop�ische Zeit schreibt 
[EMAIL PROTECTED]:

> Is it possible to create an empty context and put only selected words in? 
for 
> 
>  security-reasons, like postscript does.
>  
(i lost her mail, so by hand :)

Gabrielle answered ([EMAIL PROTECTED])
>Yes, it is, but you actually need to create a context with all the
>words set to UNSET!. You can refer to the message 95706 I posted
>to this list on 31st January for an example (you can find it on
>http://www.rebol.org/ or request it to SELMA).

I did and got something similar  to this, but was able to hack it with going 
to global scope by "/probe" instead of "probe". so for security this is not 
enough!! (Gabrielle, please don't try this with "/delete rebol.exe"!!! 
But thank you for the adding-of-contexts-example! I understand this stuff now 
much better! :)

    REBOL[]

    allowed: make object! [     ; only this two allowed, not "probe" for 
example..
     print: get in system/words 'print
     none: system/words/none
    ]
    all-unsets: use first system/words ['system]

    code: [print "Hello!"]
    malicious-code: [/probe "hello"] ; the "/" breaks out!

    bind code all-unsets
    bind code in allowed 'self
    do code

    bind malicious-code all-unsets
    bind malicious-code in allowed 'self
    do malicious-code


Gruss Volker

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