It should be possible to define a private [namespace] such that no external references to [variable]s are possible, and no invocation of namespace-local [proc]s are possible except via [namespace export]ed names. This would provide a nice degree of encapsulation, perhaps even a cheap [sandbox] and would be easy to implement. Implementation: I suggest a form of name of namespace which can't be present in a variable or proc invocation. This means an explicit namespace-path can't be constructed. -- [CMcC] 20 Mar 2005 [RS]: Sandboxes are for playing - I'd hate a closed box that says "hey, you cannot see or touch my sand" in interactive debugging... Also, with escaping as needed, any string can be the name of a variable or proc. In general, I'm more happy with Tcl's spirit "You can do anything you can think of, and more" as opposed to Bondage & Discipline languages. ----