Cleaning up conditionals

Antoon Pardon antoon.pardon at
Mon Jan 2 09:09:21 EST 2017

Op 31-12-16 om 01:26 schreef Deborah Swanson:
>> On 31 December 2016 at 10:00, Deborah Swanson 
>> <python at> wrote:
>>> Oops, indentation was messed up when I copied it into the email.
>> The indentation of your latest message looks completely 
>> broken  now, you can see it here: 
> 7758.html
> Hm, I don't know what pipermail does with whitespace but the formatting
> in the message at
> is not the same as the message I sent from Outlook.
> Again, it should have been:
> if len(l1[st]) == 0:
> 	if len(l2[st]) > 0:
> 		l1[st] = l2[st]
> elif len(l2[st]) == 0:
> 	if len(l1[st]) > 0:
> 		l2[st] = l1[st]

I just would like to point out that you could just eliminate each sub-if
and just write this as:

if len(l1[st]) == 0:
    l1[st] = l2[st]
elif len(l2[st]) == 0:
     l2[st] = l1[st]

If we look at the first branch the eliminated test would prevent the
assignment in case l2[st] is empty. But we already know l1[st] is empty.
So we are just eliminating the replacement of an empty field with an
empty field. There is no harm in that and trying to eliminate it just
makes your test unnecessarily complex.

Antoon Pardon 

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