PEP 238 (revised)

[Bruce Sass]

On Fri, 27 Jul 2001, Chris Barker wrote:
<...>
> The problem with the from __past__ statement is that we will end up with
> many different dialects of the language, all of which need to be
> supported (if it's too much work to have old versions supported, why is
> this OK?) and will need to be supported forever!

I don't think that is true.  Supporting old behaviours forever is
barely different from keeping old versions around forever, and should
be avoided for the same reasons...  at some point you need to stop
living in the __past__, so to speak.

__past__ could be integrated with __future__, and then viewed as part
of the upgrade path of a new feature... not as something that gets
plopped into Python to accommodate old code.

I see __past__ as one last chance to easily check your code to see if
the associated feature upgrade broke it, after that it is either fix
the code or have it depend on an older Python.


- Bruce