On Fri, 17 Jun 2005 16:40:56 -0600, <[EMAIL PROTECTED]> wrote: > John Reese wrote: >> I now do: >> >> if isinstance(x, list): >> >> It is my understanding that this is what people do nowadays. > > I wouldn't go that far. I don't have an isinstance check for lists > anywhere in my entire codebase. Why do you think you need to check to > see if something is of type list? Why don't you just use it as needed, > and find out, e.g.: > > try: > itr = iter(x) > except TypeError: > # do whatever you need to do if it's not iterable > else: > # do whatever you need to do if it *is* iterable > > STeVe
I'm not saying I do it a lot, but sometimes it's useful to write methods with interfaces like, well, isinstance's, whose second argument can be a single type object or a sequence of class objects. The standard conditional vs. exception tradeoffs exist here... if it's likely that x isn't iterable, I shouldn't have to incur the time and heap churn penalty of filling in sys.exc_info and its obsolete cousins, potentially rolling back the stack, etc. -- http://mail.python.org/mailman/listinfo/python-list
