[Python-Dev] Proposal for new 2to23 tool

[Guido van Rossum]

On Nov 11, 2007 7:24 PM, Jan Claeys <lists at janc.be> wrote:
> Graham wants to convert his code such that it works on both Python 2.x
> (probably even early versions of it?) & Python 3.x.  Not 2 instances of
> code, but one source that works on both 2.x and 3.x...

The transition strategy for 3.0 explicitly excludes this possibility.

For example, you couldn't catch exceptions with an error variable,
because the except clause syntax changed. You couldn't use print
except to print a single string. You couldn't use unicode string
literals; you couldn't distinguish between text and binary data in a
meaningful way.

-- 
--Guido van Rossum (home page: http://www.python.org/~guido/)