[Python-Dev] Breaking bug #411881 into manageable pieces

[Skip Montanaro]

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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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