[Python-Dev] PEP, take 2: Exception Reorganization for Python 3.0

[Phillip J. Eby]

At 09:02 PM 8/2/2005 -0400, Raymond Hettinger wrote:
>The Py3.0 PEPs are a bit disconcerting.  Without 3.0 actively in
>development, it is difficult to get the participation, interest, and
>seriousness of thought that we apply to the current release.  The PEPs
>may have the effect of prematurely finalizing discussions on something
>that still has an ethereal if not pie-in-the-sky quality to it.  I would
>hate for 3.0 development to start with constraints that got set in stone
>before the project became a reality.
>
>With respect to exception re-organization, the conversation has been
>thought provoking but a little too much of a design-from-scratch
>quality.  Each proposed change needs to be rooted in a specific problem
>with the current hierarchy (i.e. what use cases cannot currently be
>dealt with under the existing tree).  Setting a high threshold for
>change will increase the likelihood that old code can be easily ported
>and decrease the likelihood of either throwing away previous good
>decisions or adopting new ideas that later prove unworkable.  IOW,
>unless the current tree is thought to be really bad, then the new tree
>ought to be very close to what we have now.

+1.  The main things that need fixing, IMO, are the need for critical and 
control flow exceptions to be distinguished from "normal" errors.  The rest 
is mostly too abstract for me to care about in 2.x.