[Python-Dev] Repeatability of looping over dicts

[A.M. Kuchling]

On Fri, Jan 04, 2008 at 02:54:49PM -0800, Guido van Rossum wrote:
> What code would break if we loosened this restriction? I guess
> defining d.items() as zip(d.keys(), d.values()) would no longer fly,
> but does anyone actually depend on this? Just like we changed how we

http://www.google.com/codesearch?hl=en&q=+lang:python+zip+keys&start=10&sa=N
turns up a few pieces of code that would break:

trac-0.10.3/trac/versioncontrol/cache.py 
Twisted-2.2.0/twisted/pb/test/test_banana.py 
Mattricks-0.7/Mattricks/MatchPrediction.py 
FlickrUploadr-1.0.0/src/xmltramp.py 

Projects trying to stay compatible with Python versions that don't
have .items() may be more likely to use this idiom.  Some classes may
do this to implement .items(); openbabel-2.1.1/scripts/python/pybel.py
does this.  So some code will break, and I don't see a way to warn
about this problem before breaking compatibility.

--amk