[Python-Dev] Re: [Python-checkins] CVS: python/dist/src/Lib getopt.py,1.7,1.8

[Guido van Rossum]

Vladimir.Marangozov@inrialpes.fr:

> Yes. Besides, I still think that string-based exceptions are just
> convenient for quick & dirty, throw-away test scripts.

They have a hard-to-understand quirk though: the id() of the string is
used to check rather than its value, so that except "foo" doesn't
necessarily catch raise "foo"; but due to various optimization, this
usually works, and people get bent out of shape when it doesn't.
Since you have to give your exception a name, how hard is it to say

class MyError(Exception): pass

rathern than

MyError = "MyError"

?

--Guido van Rossum (home page: http://www.python.org/~guido/)