python: Exception flow: Continue to down catch block after catching?

Question

I am curious if there is a way in python to continue on within try/catch block, after you catch an exception, look at its properties, and if not relevant, then continue down the stack.

try:
    # Code
except AppleError as apple_ex:
    # look at 'apple_ex.error_code' error body, and if not relevant, 
    # continue on to next down the catch block...
    # In other words, proceed to except BananaError and so on down.
except BananaError as banana_ex:
    # ...
except Exception as ex:
    # ...

Answer 1

An AppleError is still an AppleError and not a BananaError, even if error_code is not relevant, so it makes no sense to fall through to BananaError.

You could instead define specific errors for your different error codes:

GRANNY_SMITH_ERROR = 1
MACINTOSH_ERROR = 2
class AppleError(Exception): 
    def __init__(self, error_code, *args):
        super(AppleError, self).__init__(*args)
        self.error_code = error_code

class GrannySmithError(AppleError):
    def __init__(self, *args):
        super(GrannySmithError, self).__init__(GRANNY_SMITH_ERROR, *args)

class MacintoshError(AppleError):
    def __init__(self, *args):
        super(MacintoshError, self).__init__(MACINTOSH_ERROR, *args)

Then you can try to match the specific error:

try: raise MacintoshError()
except MacintoshError as exc: print("mac")
except GrannySmithError as exc: print("granny smith")

If you do not care to distinguish between different types of apple errors, you can still trap all apple errors:

try: raise MacintoshError()
except AppleError as exc: print("generic apple")

You can combine these, for example, only doing special processing for GrannySmith, not for Macintosh:

try: raise MacintoshError()
except GrannySmithError as exc: print("granny smith")
except AppleError as exc: print("generic apple")

The important thing is to list the errors from most specific to least specific. If you test for AppleError before GrannySmithError, then it will never enter the GrannySmith block.