Fredrik Lundh <fredrik at pythonware.com> wrote: > George Sakkis wrote: > > > I won't open another can of worms here, but I'll just say that as much > > as I hate Java's stubborn insistence on OO purity, I am equally > > disturbed by Python's arbitrary-looking choices on whether some > > callable ends up a function or a method. When I talk about or > > introduce Python to outsiders, one of the toughest questions is often > > > something along the lines of "why len() is a function and not a > > method?" > > I guess those outsiders don't really understand the concept of a > "generic operation". are you sure *you* understand what that is? > it's not obvious from your your posts.
Perhaps I don't, but if you or anyone else wants to enlighten me, please make sure you include in your explanation 1) why having a "generic operation" len() that ends up looking for an ugly special *method* called __len__() makes sense, while calling directly a method len() doesn't, and 2) if "generic operations" are such a cool idea, why there aren't more of them, such as count() or index() (the former for any container type, the latter for sequence types). I don't think that defending a decision by pointing out a different bad decision in another language (Java's inconsistency between string.length and list.length()) is a particularly compelling argument, especially in an FAQ page. The ending sentences though are more convincing: "...but it's a part of Python, and it's too late to make such fundamental changes now. The functions have to remain to avoid massive code breakage". That I can buy (at least for 2.x). George _______________________________________________ Python-3000 mailing list Python-3000@python.org http://mail.python.org/mailman/listinfo/python-3000 Unsubscribe: http://mail.python.org/mailman/options/python-3000/archive%40mail-archive.com
