[Python-3000] Change to class construction?

[Phillip J. Eby]

At 11:56 PM 7/9/2007 +0300, Guido van Rossum wrote:
>  The use of the word "mapping"
>might easily be construed as implementing abc.Mapping, and then
>iteration and reading the contents would be well-defined.

I'm not sure which use of the word "mapping" you're talking 
about.  PEP 3115 is explicit that there is no specific requirements 
for the __prepare__()'d namespace; it just mentions some things that 
might be useful to have in such an object.

So, in order to replace it with a view or something, we'd want to 
change the PEP to explicitly document what is required.

Personally, I'd just as soon make it explicitly official that 
locals() in a class suite gives you the __prepare__()'d object, 
whatever it is.  If a given Python implementation can support PEP 
3115 in the first place, then it clearly knows what object to return.  ;-)