optimize 'for a, b in some_dict.iteritems()'

[srepmub]

hi all,

shedskin currently optimizes away intermediate objects (tuples, lists,
iterator objects..) for the following constructs:

for a,b in zip(..):

for i, e in enumerate(..):

the following case came up in private conversation, and seems useful
to optimize as well:

for a,b in some_dict.iter_items():

I'm busy with some other improvements, but if anyone would be
interested in looking into this.. see def visitFor in shedskin/cpp.py
and the corresponding macros in shedskin/lib/builtin/iter.hpp :-)

thanks,
mark.