On 2006-09-01, Tal Einat <[EMAIL PROTECTED]> wrote: > Tim Chase wrote: >> I'm not sure if '__iter__' is the right thing to be looking >> for, but it seems to work at least for lists, sets, >> dictionarys (via their keys), etc. I would use it because at >> least then you know you can iterate over it > > AFAIK and as seen throughout posts on c.l.py, the best way to > check if something is iterable is: > > try: > iter(obj) > except TypeError: > <obj is not iterable> > else: > <obj is iterable>
That confounds me. Of course, I'm coming from a C++, where you never want to throw an exception in a common case, hence the name 'exception'. The Python FAQ does say that raising and catching an exception is an expensive operation. I see that type-checking is good to avoid, but type-checking must be better than "abusing" exceptions in this way. Is the above really a popular idiom? If so, I guess I'll get used to it. -- Neil Cerutti -- http://mail.python.org/mailman/listinfo/python-list
