[Python-3000] pre-PEP: Procedure for PEPs with Backwards-Incompatible Changes

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    Ian> There seems to be a danger that Py3K is seen as a more friendly
    Ian> place to suggest changes than Python 2.x (or maybe that the
    Ian> python-3000 list is more friendly to these suggestions than
    Ian> py-dev), and so changes are brought up here even though they could
    Ian> be applied earlier.  This would be problematic in part because if a
    Ian> change *can* go in 2.x, it would be really good if it did, so that
    Ian> the move to 3.0 involves as few changes as possible.

There are some things which would be difficult to do cleanly in 2.x because
because of syntactic or semantic limitations.  We've agonized over a number
of changes to the language in the past few years which were made more
difficult by the preexisting bits of the language or its various
implementations.  I imagine proposals which fall into that category might
well be Py3k only.  I see no reason to implement them badly in 2.x at this
point only to break them incompatibly in 3.x.  That was why I asked about a
distinction between PEPs.

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