Modules that provide differing functionality amongst different Python versions...

[Bengt Richter]

On Sun, 21 Apr 2002 20:31:24 +0200, holger krekel <pyth at devel.trillke.net> wrote:

>On Sun, Apr 21, 2002 at 02:12:16PM -0400, Carl Banks wrote:
>> Allan Crooks wrote:
>> > Hi,
>> > 
>> > I was wondering what the best approach is on providing libraries for
>> > varying versions of Python?
>> > (...)
>
>> # Import stuff for version 2.1
>> if sys.version[:2] >= (2,1):
>>     from mymodule2_1 import *
>> 
>> # Import for version 2.2
>> if sys.version[:2] >= (2,2):
>>     from mymodule2_2 import *
>
Wouldn't you want to import from 2.2 first (and perhaps use elifs)?
(though obviously the if-tests themselves must be lowest-version compatible
if done in that order).

>this solves part of the 'code duplication' problem. Might get a bit tricky
>if you just want to define a few additional methods for some classes
>(for example 'generator versions' of methods otherwise returning lists).
>
>Ah, and by the way how is
>
>	sys.version[:2] >= (x,y) 
>
>supposed to work? On my python 2.2 
>
>	sys.version[:2] == '2.'   is True
>
>am i missing something here?
>
>	holger
>
>
He probably meant

 >>> sys.version_info
 (2, 2, 0, 'final', 0)
 >>> sys.version_info[:2]
 (2, 2)

Although 1.5.2 doesn't have this AFAIK, so

 >>> import sys, string
 >>> string.split(sys.version)[0] >= '2.2'
 1

where

 >>> string.split(sys.version)[0]
 '2.2'

might be a better idea.

Regards,
Bengt Richter