[Python-Dev] A little GC confusion

Jeremy Hylton jeremy@alum.mit.edu
Fri, 22 Feb 2002 22:59:58 -0500

[I wrote:]
> One property of types that do not have define HEAPTYPE is that their
> __module__ attribute is always __builtin__.  This makes them
> mighty hard to
> pickle.  It further suggests that every type that isn't a builtin type
> should define HEAPTYPE.

I don't think I made much sense above.  I meant to say: When my C types
didn't define HEAPTYPE, it was impossible to pickle them.  When I added the
HEAPTYPE and defined __safe_for_unpickling__ as a data member, it became
possible to pickle instances of those types.  It was far from obvious,
though, that I needed to do those two things to make pickling work.