Oh, and by the way. In addition to creating a safe namespace and selectively giving it unsafe functions, you can also remove functions from a safe namespace.
For instance, suppose you wanted to run code in a safe environment, but you didn't want it to be able to print (using pr, prn, prt, etc.) You could use this:
(= env (new-namespace))
(= env.'disp nil)
; do something with env
Like I said, it's very flexible. You have complete control over what is/isn't in a namespace. You can execute each module in it's own namespace, or combine them however you wish, etc. It has a very simple core, but has many many potential uses.
