On 23 October 2013 08:58, Albert-Jan Roskam <fo...@yahoo.com> wrote: > So the built-in 'len()' is *really* a function, but calls to len() > implemented by __len__ are method calls *disguised* as function calls? I > sometimes find it easier to write calls to special methods the "normal" way, > e.g. instead of "x + y" just write it like "x.__add__(y)" This makes special > methods more like other methods and therefore easier to understand, to me at > least.
Please don't do that. Firstly it looks horrible. Secondly they're not equivalent. The equivalent of x + y is operator.add(x, y) but don't use that either. It's not easier to understand and it's less efficient. When you wrate a+b the interpreter actually calls a bunch of different methods: a.__add__(b), b.__radd__(a), a.__coerce__(b) etc. I don't know the full sequence and it's not consistent across Python implementations. Eryksun recently posted a good example showing how a == b is handled: https://mail.python.org/pipermail/tutor/2013-July/097110.html Oscar _______________________________________________ Tutor maillist - Tutor@python.org To unsubscribe or change subscription options: https://mail.python.org/mailman/listinfo/tutor
