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Date: Thu, 30 Apr 2015 04:18:06 -0400
From: Dave Angel <davea@davea.name>
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Subject: Re: Let exception fire or return None
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On 04/30/2015 03:43 AM, Cecil Westerhof wrote:
> I have a function to fetch a message from a file:
>      def get_indexed_message(message_filename, index):
>          """
>          Get index message from a file, where 0 gets the first message
>          """
>
>          return open(expanduser(message_filename), 'r').readlines()[index].rstrip()
>
> What is more the Python way: let the exception fire like this code
> when index is to big, or catching it and returning None?
>
> I suppose working zero based is OK.
>

Fire an exception.

One advantage is that the exception will pinpoint exactly which line of 
the function had a problem.



-- 
DaveA