function taking scalar or list argument

[Terry Reedy]

"Steven Bethard" <steven.bethard at gmail.com> wrote in message
news:loom.20040824T052140-517 at post.gmane.org...
> Well, you can always test for the protocol, e.g.:
>
> def twice(x):
>     if hasattr(x, "__iter__"):
>         return map(twice, x)

In 2.2.1:
>>> hasattr([1,2,3], '__iter__')
0
so this does not seem to work as you seem to expect.  hasattr(iter(x),
'__iter__') will.

Terry J. Reedy