[Python-Dev] PEP 3000 and iterators

James Y Knight foom at fuhm.net
Sun Sep 11 05:57:58 CEST 2005

On Sep 10, 2005, at 6:07 PM, Lisandro Dalcin wrote:

> I had that in mind when I wrote my post; changing types is not the
> way, that will not work. That is why I proposed __future__ (I really
> do not know very well the implementation details of that feature)
> because I think the parser/compiler can (magically) make the
> replacements, e.g.  dict.items -> dict.iteritems for Py2.X series in
> codes *using* dicts . Do you think something like this could be
> implemented in a safer way?

No, that cannot work. However, there is a very obvious and trivial  
solution. Do not remove dict.iteritems in Py 3.0. Py2.X programs  
wishing forward compat can   avoid dict.items and use instead  
dict.iteritems. In Py3.0, dict.items becomes a synonym for  
dict.iteritems and programs that don't care about compat with 2.X can  
just use dict.items from then on. And everybody can be happy. A small  
number of redundant methods is a small price to pay for compatibility.


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