[Zope] Counting the elements of a result in a ZCatalog

[Tino Wildenhain]

Hi,

Marco Bizzarri wrote:
...
>> if result:
>>   result_len = results.actual_result_count
>> else:
>>   result_len = 0
>>
>> return result_len
>>
...
> 
> Thanks for your answer, but there is something I do not understand:
> 
> if results:
> 
> an empty result from ZCatlog is false in a boolen condition?

Yes, thats standard Python behavior, empty lists, dictionaries
and similar objects are assumed "False" when used as boolean.

This means you could even write it this way:

return (results and results.actual_result_count) or 0

in python2.5 (not yet supported by Zope) even:

return results.actual_result_count if results else 0

Cheers
Tino

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