Martin v. Löwis wrote: > Robert Kern schrieb: > >>>As I unification mechanism, I think it is insufficient. I doubt it >>>can express all the concepts that ctypes supports. >> >>What do you think is missing that can't be added? > > > I can factually only report what is missing. Whether it can be added, > I don't know. As I just wrote in a few other messages: pointers, > unions, functions pointers, packed structs, incomplete/recursive > types. Also "flexible array members" (i.e. open-ended arrays). >
I understand function pointers, pointers, and unions. Function pointers are "supported" with the void data-type and could be more specifically supported if it were important. People typically don't use the buffer protocol to send function-pointers around in a way that the void description wouldn't be enough. Pointers are also "supported" with the void data-type. If pointers to other data-types were an important feature to support, then this could be added in many ways (a flag on the data-type object for example is how this is done is NumPy). Unions are actually supported (just define two fields with the same offset). I don't know what you mean by "packed structs" (unless you are talking about alignment issues in which case there is support for it). I'm not sure I understand what you mean by "incomplete / recursive" types unless you are referring to something like a node where an element of the structure is a pointer to another structure of the same kind (like used in linked-lists or trees). If that is the case, then it's easily supported once support for pointers is added. I also don't know what you mean by "open-ended arrays." The data-format is meant to describe a fixed-size chunk of data. String syntax is not needed to support all of these things. What I'm asking for and proposing is a way to construct an instance of a single Python type that communicates this data-format information in a standardized way. -Travis _______________________________________________ Python-Dev mailing list Python-Dev@python.org http://mail.python.org/mailman/listinfo/python-dev Unsubscribe: http://mail.python.org/mailman/options/python-dev/archive%40mail-archive.com
