[Python-Dev] Capabilities / Restricted Execution

[Phillip J. Eby]

At 03:36 AM 7/11/2006 -0700, Talin wrote:
>I thought a little bit more about Guido's comment that you can hide
>Python objects in a C wrapper class. However, as I was trying to sleep,
>I realized that you don't even need C to do it.
>
>The trick is to store the object reference as a closure variable.
>Assuming that there's no mechanism to directly access such variables,
>you can effectively have 'private' variables.

A function's func_closure contains cell objects that hold the 
variables.  These are readable if you can set the func_closure of some 
function of your own.  If the overall plan includes the ability to restrict 
func_closure setting (or reading) in a restricted interpreter, then you 
might be okay.