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Author blackfawn
Recipients BreamoreBoy, barry, blackfawn, brett.cannon, cvrebert, ezio.melotti
Date 2015-04-14.21:29:19
SpamBayes Score -1.0
Marked as misclassified Yes
Message-id <>
So, this is actually impossible to do.
Since exceptions are c-level classes, adding members to ValueError means anything that multiple-inherits from ValueError and any other complex exception gets a multiple bases layout conflict. There's already one such class - _pyio.UnsupportedOperation inherits both ValueError and OSError - but the bigger issue is that this would break compatibility.

After discussing it (face-to-face) with a bunch of core devs, I think the only reasonable course of action is to close the issue and never speak of this again.
Date User Action Args
2015-04-14 21:29:19blackfawnsetrecipients: + blackfawn, barry, brett.cannon, ezio.melotti, cvrebert, BreamoreBoy
2015-04-14 21:29:19blackfawnsetmessageid: <>
2015-04-14 21:29:19blackfawnlinkissue18166 messages
2015-04-14 21:29:19blackfawncreate