[Edu-sig] Python 3.0a: investigating changes

[kirby urner]

So I'm in a Portland coffee shop, iTunes on the speakers, daughter
reading a novel.

I remember Guido saying something about 'next' changing a little.

What I'm finding tonight is the old some_generator.next() syntax
is breaking (by design I assume), while next(some_generator)
works great.

What's getting triggered under the hood is __next__, which of
course you can trigger directly.

>>> thegen = (i for i in range(10))
>>> thegen
<generator object at 0xb7c9430c>
>>> type(thegen)
<type 'generator'>
>>> thegen.next()
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
AttributeError: 'generator' object has no attribute 'next'
>>> dir(thegen)
['__class__', '__delattr__', '__doc__', '__eq__', '__format__',
'__ge__', '__getattribute__', '__gt__', '__hash__', '__init__',
'__iter__', '__le__', '__lt__', '__ne__', '__new__', '__next__',
'__reduce__', '__reduce_ex__', '__repr__', '__setattr__', '__str__',
'close', 'gi_frame', 'gi_running', 'send', 'throw']
>>> next(thegen)
0
>>> next(thegen)
1
>>> next(thegen)
2
>>> def fibbo(a=0,b=1):
...    while True:
...       yield a
...       a,b = a+b, a
...
>>> somegen = fibbo()
>>> type(somegen)
<type 'generator'>
>>> type.next()
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
AttributeError: type object 'type' has no attribute 'next'
>>> next(somegen)
0
>>> next(somegen)
1
>>> next(somegen)
1
>>> somegen.__next__()
2
>>> somegen.__next__()
3
>>> somegen.__next__()
5
>>> somegen.__next__()
8
>>> somegen.__next__()
13
>>> somegen.__next__()
21
>>>

and so on.

Kirby