On 2021-05-31, Greg Ewing <greg.ew...@canterbury.ac.nz> wrote: > On 31/05/21 9:13 am, Jon Ribbens wrote: >> No, I said it pretends to be a *data* attribute. > > I don't think it's pretending to be anything. From the outside, > it's just an attribute.
>From the outside, it's just a *data* attribute. Which, from the inside, it isn't. Hence "pretending". > Data attributes are more common than non-data attributes, so > we tend to assume that an attribute is a data attribute until > told otherwise. But that's just our psychological bias, not > because of any pretence on the part of properties. None of that is true. You can tell something's definitely not a data attribute if you have to put brackets after its name to call it as a method to invoke its function or retrieve the value it returns. Accessing a data attribtue is efficient and has no side effects, unless someone's doing some unusual and probably inadvisable hackery behind the scenes. Calling a method can do literally anything. > Also, there's a sense in which *all* attributes are properties. > At the lowest level, all attribute accesses end up calling > a method. It's just that in most cases the method is implemented > in C and it looks up a value in the object's dict. Sure, if we take the "lowest level" and pretend there are no higher-level structures it's all just electrons doing apparently random things and there's nothing more to be said about it. -- https://mail.python.org/mailman/listinfo/python-list
