Steven D'Aprano <[EMAIL PROTECTED]> wrote: > > Instead of doing: > > > if callable(function): function() > > you should do: > > try: > function() > except TypeError: > pass > > > That should work for most uses of callable(), but isn't quite the > same. (What if function() has side-effects, or is expensive, and you > want to determine if it is callable, but not actually call it _now_?)
The replacement for callable(x) is simply hasattr(x, '__call__'). Once upon a time it may have been that functions didn't have a __call__ attribute (I haven't checked back on really old Pythons top see if this was the case), but these >> Also, what is the replacement of reduce? I think I remember seeing >> somewhere that lists comprehension would be (but also remember the >> advise that reduce will be quicker). > > No, a list comprehension isn't equivalent to reduce(). There is no > replacement for reduce(). <snip> There are of course several replacements for specialised uses of reduce: sum, any, all. There is no general purpose replacement, but you can write one in a few lines if you really need it. > > It's a shame really. Oh well, maybe it will sneak back in via a > functional module, or itertools, or something. What a waste, what a > waste. I'm sure it will reappear in some other module, but that's the correct place for a little used function, not in builtins. -- http://mail.python.org/mailman/listinfo/python-list
