[XML-SIG] Deep copy of an element from one document to another

[Uche Ogbuji]

On Wed, 2002-06-19 at 09:03, Fred L. Drake, Jr. wrote:
> 
> Uche Ogbuji writes:
>  > I like this idea, except iterators are 2.2 only.  I suppose the
>  > __iter__ function would be harmless in an older version, but it
>  > puts the onus on the user to write his code portably, probably
>  > restoring the verbosity the iterator would have minimized.
> 
> Regarding the iterator:  it's worse than that, though:  I used the
> "yield" keyword, which will cause a SyntaxError in Python 2.1.x and
> earlier.  That might be a problem for some people, and is more tedious
> to work around.  ;-(

Yes.  At least iterators don't introduce new syntax.  I ran into the
generator problem a few weeks back when I tried to introduce more
efficient DOM iterator code.  No way to make a condition around a new
keyword.  I even tried fiddling with distutils so that it would install
one file if Python 2.2 was installed, and another for older versions,
but this was too much of a terror.  Before I gave up, I considered a
hack that would probably work, but was too ugly for contemplation:

exec("yield")

I decided against this  :-)


-- 
Uche Ogbuji                                    Fourthought, Inc.
http://uche.ogbuji.net    http://4Suite.org    http://fourthought.com
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