python stop exception passing

Question

I have a custom InvalidError, and I want my function handles two kinds of errors: one is InvalidError, the other are all other errors. I tried in this way:

try:
   a = someFunc()
   if a:
      # do things
   else:
      raise InvalidError('Invalid Error!')
except InvalidError as e:
      return "Invalid"
except Exception as ex:
      return "Other"

But seems I will get Other either way. How can I achieve my functionality in right way?

Have you defined InvalidError as a class extending Exception class ? — Mangu Singh Rajpurohit, Nov 06 '15 at 09:21
Possible duplicate of [Manually raising (throwing) an exception in Python](http://stackoverflow.com/questions/2052390/manually-raising-throwing-an-exception-in-python) — JasmineOT, Nov 07 '15 at 12:28

score 0 · Answer 1 · edited Nov 06 '15 at 09:24

0

Can you tell us how you created you InvalidError class? It is working.

class InvalidError(Exception):
   pass

>>> try:
...    raise InvalidError("dsfsdf")
... except InvalidError as my_exception:
...    print "yes"
... except Exception as e:
...    print "No"
... 
yes

edited Nov 06 '15 at 09:24

Mangu Singh Rajpurohit

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answered Nov 06 '15 at 09:21

Sanch

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ShaneOC · Answer 2 · 2015-11-06T09:32:36.240

0

One way of doing this would be to create a context manager class. Within the contect manager you can ignore whatever error you like,

E.g.

class ctx_mgr:

def __enter__(self):
    cm = object()
    return cm    

def __exit__(self, exc_type, exc_value, exc_tb):
    return (exc_type == InvalidError)

with ctx_mgr: a = someFunc()

edited Nov 06 '15 at 09:32

answered Nov 06 '15 at 09:22

ShaneOC

1
2

python stop exception passing

2 Answers2