On 09/07/13 05:47, Dave Angel wrote:
On 07/08/2013 01:57 PM, Jim Mooney wrote:
On 8 July 2013 00:12, Steven D'Apranocatching ArithmeticError
further on), please use a custom exception
Well, an Arithmetic Error was better than bubbling up to a totally general
one. I'm not sure how do custom error code. Short example, please ;')
Jim
I think a ValueError might be best.
[...]
class TooHugeError (ValueError):
pass
I would normally agree, but in Jim's code the exception is purely being used
for internal flow control, it is not being exposed to the caller. So I wouldn't
inherit from ValueError, I'd keep this a completely independent exception. I
wouldn't even call it an Error, since it's actually a limitation of Jim's code,
not an actual error.
Also, since Jim's code already catches ValueError, he would need ensure that he
catches this *first*, otherwise it will be caught by the ValueError handler:
try:
raise TooHugeError
except TooHugeError: # this must come first
...
except ValueError: # otherwise this will catch it
...
Whereas if you keep the custom exception independent, the order of except
clauses doesn't matter.
class TooHuge(Exception):
pass
try:
raise TooHuge
except ValueError:
print("bad value")
except TooHuge:
print("caught it")
--
Steven
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