[Python-Dev] capability-mediated modules (was: python-dev Summary for 2003-03-01 through 2003-03-15)

Ben Laurie ben@algroup.co.uk
Thu, 20 Mar 2003 10:33:26 +0000

Greg Ewing wrote:
> Zooko <zooko@zooko.com>:
>>Now what I would *like* is that instead of doing "import os" to load code, 
>>instead the caller provides, or doesn't provide the os module as part of the 
>>construction/invocation of A.
>>I don't have a clear idea yet of how that could be implemented in a 
>>Pythonic, compatible way.
> Maybe, instead of there being one ultra-global namespace for importing
> modules from, it should be part of a function's environment. By
> default a function invocation would inherit the "import environment"
> of it's caller, but the caller could override this to provide a more
> restricted environment.

Inheriting things is not the capability way. Passing capabilities that 
allow imports is, of course, but isn't very Pythonic. I'm not sure 
there's a neat way to fix this that keeps both camps happy.

> This would be equivalent to passing in a set of allowable
> modules as an implicit parameter to every call.

Making it explicit would make me happy. Can you pass parameters to an 



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