There are some rules for type objects that I'm not sure are written down anywhere. For example, a. Every type must have a dealloc function. b. If a type defines a number add and is also a sequence you must define sequence concat. Failure to obey these rules results in code crashes of the unpleasant sort. In a C++ facility to make it easier to write correct extensions to Python, I can fix a few of these problems. For example, in case (a) I can supply a default dealloc and in case (b) set the concat to be the same as the add if the concat is not supplied. So, what are the rest of the rules for type objects? _______________ C++-SIG - SIG for Development of a C++ Binding to Python send messages to: c++-sig@python.org administrivia to: c++-sig-request@python.org _______________