A counter-counter-proposal for PEP 236: #pragma( nested_scopes)

[Tim Peters]

[Jeremy Hylton]
> ...
> A word of clarification: __future__ isn't about experimental
> features.  Instead it is for bleeding edge users to use a new feature
> in release X even though the feature won't be standard until release
> Y, where X < Y.
>
> If we want to do experimental stuff, we should probably do something
> like:
>
> from __possible_world__ import __future__
> from __future__ import ...

Hmm.  Maybe that's why I so dislike Martin's attempt to hijack PEP 236:  his
current formulation of an alternative leaves only the raw names, without the
__future__ or __possible_world__ qualifiers.  We have a clear taxonomy in
mind when we're doing this stuff, but that's lost in an all-purpose
"directive" statement.  So, over time, only the experts who introduced
various directive gimmicks will remember where their particular raw names fit
in the grander scheme.

Back to your point <wink>, I expect that until release Y happens, it probably
*is* most correct to view a __future__ feature as experimental.  Indeed,
that's why PEP 236 says a MandatoryRelease value may become None (meaning
that the feature was withdrawn).  But it's experimental in the sense that
while it *may* be withdrawn, the presumption is that it won't be -- it's not
just random "trying things out" (which is how I suspect you read /F's use of
the word, and for which __possible_world__ (whatever) would be more
appropriate).

words-words-and-more-words-ly y'rs  - tim