[Python-Dev] A little GC confusion

Jeremy Hylton jeremy@alum.mit.edu
Fri, 22 Feb 2002 22:51:28 -0500

[David Abrahams]
> I /guess/ there's a bug in my code if you measure it against the standard
> that says "if it doesn't work with the current Python source code, it's
> buggy". I'd consider that standard a bit more legitimate if I could find,
> for example, a mention of Py_TPFLAGS_HEAPTYPE *anywhere* in the
> Python docs.

I've been struggling with the meaning of the various TPFLAGS myself.  I
don't think it's documented anywhere, and I don't think anyone except Guido
really understands what all the flags mean.

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.

There are lots of other cases affected by HEAPTYPE.  I imagine you've done
the same grep that I did.