Hey,
As part of pickle4, I found it interesting to add the possibility
of pickling bound functions (instance methods). This is done by
pickling f.__self__ and f.__func__ separately, and then adding
a BIND opcode to tie them together.
While this appears to work fine for python methods (non-builtin), some
issues arise with builtins. These are partly caused because
not all builtin function types support __func__, partly because
not all of them fill __module__ when they should and partly
because there are many (7) types a function can actually have:
ClassMethodDescriptorType = type(??)
BuiltinFunctionType = type(len)
FunctionType = type(f)
MethodType = type(A().f())
MethodDescriptorType = type(list.append)
WrapperDescriptorType = type(list.__add__)
MethodWrapperType = type([].__add__)
AllFunctionTypes = (ClassMethodDescriptorType, BuiltinFunctionType,
FunctionType, MethodType, MethodDescriptorType,
WrapperDescriptorType, MethodWrapperType)
repr(AllFunctionTypes) = (