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[REBOL] Re: Please help me to promote REBOL

From: lmecir:mbox:vol:cz at: 11-Nov-2003 20:55

Hi, [SunandaDH--aol--com] napsal(a):
>Amending my original suggestion to take into account TRY'd code unsetting >'true or 'set, I'd suggest this for a simple, foolproof way to catch an error: >don't use 'true, use 1: > >if error? error-code: try [do %config.r 1] > [probe disarm error-code] > >if error? error-code: try [print "" 1] > [probe disarm error-code] > >It's harder to unset 1. >
This may be as safe as you want it to be, but it is not convenient (append something just to be sure it returns a value). I prefer my Default function for this purpose instead.
>But the DO'd code could still have messed with 'if or 'error? or 'probe. > >That raises a wider question about DOing untrusted code. > >If you don't trust it at all, maybe it's better not to DO it in the first >place. > >To seriously stop it messing things up while debugging: > >protect-system >unset 'unprotect >if error? error-code: try [do %config.r 1] > [probe disarm error-code] >
This is not sufficient as I have proven long time ago. (Rebol functions are mutable, which means, that you can change the behaviour of any function - even a native without unprotecting the word referring to it. :-(