Guido van Rossum wrote: [me, about embedding tracebacks into frames]
Does this make sense? Do I miss something?
Yes. It is quite possible to have multiple stack traces lingering around that all point to the same stack frames.
Oh, I see. This is a Standard Python specific thing, which I was about to forget. In my version, this can happen, too, unless you are in a continuation-protected context already. There (and that was what I looked at while debugging), this situation can never happen, since an exception creates continuation-copies of all the frames while it crawls up. Since the traceback causes refcount increase, all the frames protect themselves. Thank you. I see it is a stackless feature. I can implement it if I put protection into the core, not just the co-extension. Frames can carry the tracebacks under the condition that they are protected (copied) if the traceback fields are occupied. Great, since this is a rare condition. Thanks again for the enlightment - chris -- Christian Tismer :^) <mailto:tismer@appliedbiometrics.com> Applied Biometrics GmbH : Have a break! Take a ride on Python's Kaunstr. 26 : *Starship* http://starship.python.net 14163 Berlin : PGP key -> http://wwwkeys.pgp.net PGP Fingerprint E182 71C7 1A9D 66E9 9D15 D3CC D4D7 93E2 1FAE F6DF where do you want to jump today? http://www.stackless.com