[Python-Dev] Pre-PEP: Exception Reorganization for Python 3.0

Greg Ewing greg.ewing at canterbury.ac.nz
Tue Aug 2 04:57:40 CEST 2005

Brett Cannon wrote:

> The problem with subclassing NotImplementedError is you need to
> remember it is used to signal that a magic method does not work for a
> specific type and thus should try the __r*__ version.

No, that's done by *returning* NotImplemented, not by
raising an exception at all.

Greg Ewing, Computer Science Dept, +--------------------------------------+
University of Canterbury,	   | A citizen of NewZealandCorp, a	  |
Christchurch, New Zealand	   | wholly-owned subsidiary of USA Inc.  |
greg.ewing at canterbury.ac.nz	   +--------------------------------------+

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