On Wed, 25 Jul 2007 11:58:40 -0700, [EMAIL PROTECTED] wrote:
> You can use the built-in dir() function to determine whether or not
> the __iter__ method exists:
Doesn't work:
In [58]: is_iterable('hello')
Out[58]: False
But strings *are* iterable.
And just calling `iter()` doesn't work either:
In [72]: class A:
....: def __getitem__(self, key):
....: if key == 42:
....: return 'answer'
....: raise KeyError
....:
In [73]: iter(A())
Out[73]: <iterator object at 0xb7829b2c>
In [74]: a = iter(A())
In [75]: a.next()
---------------------------------------------------------------------------
<type 'exceptions.KeyError'> Traceback (most recent call last)
/home/bj/<ipython console> in <module>()
/home/bj/<ipython console> in __getitem__(self, key)
<type 'exceptions.KeyError'>:
So there's no reliable way to test for "iterables" other than actually
iterate over the object.
Ciao,
Marc 'BlackJack' Rintsch
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