[Python-Dev] Breaking bug #411881 into manageable pieces (original) (raw)

Skip Montanaro skip@pobox.com
Tue, 19 Mar 2002 14:59:01 -0600

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Just to make sure nobody's confused by the timing of this note: none of this has anything to do with 2.2.1.

About a year ago, Itamar Shtull-Trauring filed a bug report about the use of unqualified except clauses in the standard library. Over the past year a number of instances have been corrected, but many remain. I made a pass through those that remain and tried to break them into four groups:

* Obviously okay, because the code must potentially recover from just
  about anything.  Modules like repr.py fall into this category.

* Not worth fixing, because the except: occurs in situations that would
  not affect application code (such as in module tests).

* Instances that should probably be fixed because it appears only a
  narrow set of exceptions could be raised by the code called from their
  try: blocks.

* I Trust Tim (tm).

I'd like to break this bug into multiple pieces by

* open a separate bug for each module that uses unqualified except
  clauses that don't obviously need to guard against random exceptions
  (see my notes below).

* for those uses that are obviously okay or don't seem worth fixing, add
  a short comment to the code explaining why it's okay in the
  neighborhood of the use.

* close bug #411881 with a reference to the new bugs spawned by this
  exercise.

While this will increase the number of open bugs, it will make this issue more tractable. As currently constituted, I don't see this bug report ever getting closed.

Attached are the notes I took while picking through the source.

Skip

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