[Twisted-Python] iterators/generator

[Clark C. Evans]

Hello.  I'd like to write my 'user' level code with generators,
and thus, was thinking that new code could perhaps be at least
generator friendly... what do you think:

1.  We add the following code fragment somewhere in a python.util
    or equivalent:

    # primative support iterators for 2.1
    try:
       StopIteration = StopIteration
       iter = iter
    except:
       class StopIteration(Exception): pass
       class _ListIterator:
           def __init__(self,lst):
               self.lst = list(lst)
           def next()
               if self.lst: return self.lst.pop(0)
               else: raise StopIteration
       def iter(lst):
           if type(lst) == type([]) or type(lst) == type(tuple()):
               return _ListIterator(lst)
           else:
               return lst
   
2. Then, code within twisted which could possible accept an 
   iterator or generator could be written like this. 

      import python.twisted.util
      try:
           itr = util.iter(getIterator())
           val = itr.next()
           while 1:
              doSomething(val)
              val = itr.next()
      except util.StopIteration: pass

Just thoughts... using generators from 'user' land is really
very useful, and it'd be nice if lower levels of Twisted allowed
for this by a mechanism similar to the above.

Clark