[Python-Dev] Why are contexts also managers? (was r45544 - peps/trunk/pep-0343.txt)

Wed Apr 19 15:00:25 CEST 2006

On Wed, Apr 19, 2006 at 10:00:21PM +1000, Nick Coghlan wrote:
> And the parenthetical comment was completely backwards and should have read:
>> (This means that all context managers are contexts, but not all contexts 
> are
> context managers).
>> The reason for recommending that context managers should be contexts is 
> similar to the reason that iterators should be iterables - so that doing 
> the __context__() call manually will still give you something that can be 
> used in a with statement.

So the intention is to enable something like:
ctx = lock.__context__()
with ctx:
 ...
Which works as long as people don't try to use the context in two
nested 'with' statements. Fair enough. I don't think I'll suggest
doing this in the "What's New", though. :)
--amk