> When would I use PyObject_SetAttrString/tp_dictoffset instead of tp_members?
When I have a variable list of attributes, and cannot statically know what those attributes might be. > I have a predefined set of members, some of which are optional. Having optional fields is also a good reason. > The problem > I had with an embedded dictionary was that I can't see its elements using > "dir()". How so? That should work fine. > Now I just converted to using tp_members, and it still seems to > work correctly for the cases I tested. So how do you do optional fields now? In particular, how would you do optional integers? > Even better, I can declare the fields > as read-only then and add doc-strings. So, I wonder, what made the original > author[2] use tp_dictoffset instead? Most likely, it was the simplest approach. This code only wants to set the attributes, and never read them. It's easier to maintain: if you want to add a field with tp_members, you have to change multiple places, and you have to consider garbage collection (assuming you have embedded objects). With tp_dictoffset, adding another attribute is easy. Regards, Martin -- http://mail.python.org/mailman/listinfo/python-list
