Domain Specific Language security

Is there a way to write a DSL which limits the access by a user? Since this is Ruby, they could write any arbitrary expression such as   MyModel.delete_all

My users would not do this on purpose, but perhaps by accident. I have read some about Sandboxes, but don't see how it would prevent something like this.

Thanks in advance, Don Mc

Dale,   Thanks! That is exactly what I needed.

Regards, Don McClean