itertools to iter transition (WAS: Pre-PEP: Dictionary accumulator methods)

[Steven Bethard]

Jack Diederich wrote:
 >
 > itertools to iter transition, huh?  I slipped that one in, I mentioned
 > it to Raymond at PyCon and he didn't flinch.  It would be nice not to
 > have to sprinkle 'import itertools as it' in code.  iter could also
 > become a type wrapper instead of a function, so an iter instance could
 > be a wrapper that figures out whether to call .next or __getitem__
 > depending on it's argument.
 > for item in iter(mylist).imap:
 >   print item
 > or
 > for item in iter.imap(mylist):
 >   print item

Very cool idea.  I think the transition from
     itertools.XXX(iterable, *args, **kwargs)
to
     iter.XXX(iterable, *args, **kwargs)
ought to be pretty easy.  The transition from here to
     iter(iterable).XXX(*args, **kwargs)
seems like it might be more complicated though -- iter would have to 
return a proxy object instead of the object returned by __iter__[1].  I 
guess it already does that for objects that support only the __getitem__ 
protocol though, so maybe it's not so bad...

STeVe

[1] And you'd probably also want to special-case this so that if iter() 
was called on an object that's already an instance of iter, that the 
object itself was returned, not a proxy.