Python moratorium and the future of 2.x

Posted Nov 12, 2009 14:19 UTC (Thu) by bartoldeman (guest, #4205)
In reply to: Python moratorium and the future of 2.x by mjthayer
Parent article: Python moratorium and the future of 2.x

It's possible to write code that works in both, though it may not be particularly elegant, especially if you use unicode strings. You'd need to use things like

"".encode("ascii").join(slist)

instead of just

"".join(slist)

b"".join(slist)

if slist is a list of byte strings. And use

    try:
        f = open(filename,mode)
    except IOError:
        s = sys.exc_info()[1]

instead of

    except IOError, s:

    except IOError as s:

Though it also depends on your 2.x baseline; 2.6 already supports a lot of the 3.x syntax. Supporting all the way up from less than 2.2 (not to mention 1.5.2) is going to be much more painful though, as 2.1 supports has_key() but not "in" for dictionaries, and 3.x is the other way around.