Re: breaking out of outer loops

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From	Terry Reedy <tjreedy@udel.edu>
Newsgroups	comp.lang.python
Subject	Re: breaking out of outer loops
Date	Mon, 7 Mar 2016 21:54:23 -0500
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On 3/7/2016 6:49 PM, Chris Angelico wrote:
> On Tue, Mar 8, 2016 at 10:42 AM, Chris Kaynor <ckaynor@zindagigames.com> wrote:
>> And the same rough example, using an exception without a function:
>>
>> for file in files:
>>      try:
>>          for line in file:
>>              section = line.split()
>>              for section in line:
>>                  if sectionCorrupt:
>>                      raise Exception('Section corrupt') # You probably want
>> more details here, for possible manual repair. You could also have a custom
>> exception class for more control.
>>      except Exception as e:
>>          print('Failed to process the file {} with error {}.'.format(file,
>> str(e))) # Probably should also print the entire traceback to aid in
>> repairing errors, especially if they are due to a bug in the code, but this
>> is the rough idea.
>
> Yes, although I would more strongly suggest the custom exception
> class. In fact, the way I'd word it is: Never raise Exception, always
> a subclass. Otherwise it's too easy to accidentally catch something
> elsewhere in the code (a ValueError or TypeError or even
> AttributeError).

I would consider raising and catching StopIteration.

-- 
Terry Jan Reedy

Thread

breaking out of outer loops Fillmore <fillmore_remove@hotmail.com> - 2016-03-07 18:09 -0500
  Re: breaking out of outer loops Ian Kelly <ian.g.kelly@gmail.com> - 2016-03-07 16:17 -0700
    Re: breaking out of outer loops Fillmore <fillmore_remove@hotmail.com> - 2016-03-07 18:21 -0500
      Re: breaking out of outer loops Chris Kaynor <ckaynor@zindagigames.com> - 2016-03-07 15:42 -0800
      Re: breaking out of outer loops Chris Angelico <rosuav@gmail.com> - 2016-03-08 10:49 +1100
      Re: breaking out of outer loops Terry Reedy <tjreedy@udel.edu> - 2016-03-07 21:54 -0500
  Re: breaking out of outer loops Rob Gaddi <rgaddi@highlandtechnology.invalid> - 2016-03-07 23:29 +0000
    Re: breaking out of outer loops Fillmore <fillmore_remove@hotmail.com> - 2016-03-07 18:40 -0500
  Re: breaking out of outer loops Chris Angelico <rosuav@gmail.com> - 2016-03-08 10:47 +1100
  Re: breaking out of outer loops Fillmore <fillmore_remove@hotmail.com> - 2016-03-07 19:02 -0500
    Re: breaking out of outer loops Chris Angelico <rosuav@gmail.com> - 2016-03-08 11:08 +1100
      Re: breaking out of outer loops Fillmore <fillmore_remove@hotmail.com> - 2016-03-07 19:13 -0500
        Re: breaking out of outer loops Joel Goldstick <joel.goldstick@gmail.com> - 2016-03-07 19:21 -0500
  Re: breaking out of outer loops Mark Lawrence <breamoreboy@yahoo.co.uk> - 2016-03-08 00:36 +0000
  Re: breaking out of outer loops Mark Lawrence <breamoreboy@yahoo.co.uk> - 2016-03-08 03:45 +0000

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