[Tutor] question concerning Boolean operators

[jim stockford]

    i'm guessing assignment, which actually associates
a reference, will skip referencing an identifier to a null
and will make the association (assignment) to the first
non-null value in the expression, which is string2 in
this case. that the identifier is non_null is immaterial;
you could write
 >>> string1, string2, string3 = '', 'Trondheim', 'Hammer Dance'
 >>> jackson = string1 or string2 or string3
 >>> jackson
'Trondheim'


On Mar 20, 2008, at 4:32 PM, Guba wrote:

> Dear list,
>
> from Guido's tutorial:
>
> It is possible to assign the result of a comparison or other Boolean
> expression to a variable. For example,
>
> 	>>> string1, string2, string3 = '', 'Trondheim', 'Hammer Dance'
> 	>>> non_null = string1 or string2 or string3
> 	>>> non_null
> 	'Trondheim'
>
> How does this work?? How does Python know that we are looking for
> non_null? After all, we don't provide this information here, right? (I
> take non_null is a variable.)
> I must be missing something... Can anyone help?
>
> Many thanks,
>
> Guba
>
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