tadman has asked for the wisdom of the Perl Monks concerning the following question:

Is it possible to turn Perl into a "multi-user" language using the Safe module? The idea is to allow user code to be loaded and executed in the context of a larger script, but that access would be strictly controlled and that the range of operators available would be limited to limit access. This would allow users to write quick macros, math functions, and the like, without being able to run system commands, create files, trash global variables, etc.

Safe understandably carries this disclaimer:
WARNING The authors make no warranty, implied or otherwise, about the suitability of this software for safety or security purposes.
Is this because Safe isn't really safe, or is this just an obligatory disclaimer? Is it theoretically secure, at least?

I understand that this might be fundamentally a Bad Idea, but stripping down Perl seems a lot easier than writing a Perl-like scripting language from the ground up.