Problem with -3 switch

Steve Holden steve at
Mon Jan 12 09:05:48 CET 2009

Carl Banks wrote:
> On Jan 9, 6:11 pm, John Machin <sjmac... at> wrote:
>> On Jan 10, 6:58 am, Carl Banks <pavlovevide... at> wrote:
>> Steve & Cliff are talking about the rather small subset of Python that
>> is not only valid syntax in both 2.x and 3.x but also has the same
>> meaning in 2.x and 3.x.
> That would be a crippled language, yes.  But I do not believe that's
> what Steve and Cliff are referring to.  Steve wrote of "running your
> code through 2to3", and that was what Cliff followed up to, so I
> believe they are both referring to writing valid code in 2.6 which is
> able to be translated through 2to3, and then generating 3.0 code using
> 2to3.  That is not a crippled language at all, just a PITA sometimes.
Correct. The recommended way of maintaining a dual-version code base is
to paraphrase your 2.6 code in such a way that the 2to3 converter will
produce correct 3.0 code that required no further attention. If you
don't do this you are making a rod for your own back.

Steve Holden        +1 571 484 6266   +1 800 494 3119
Holden Web LLC    

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