James Cunningham wrote:
> On 2006-11-10 15:24:50 -0500, Bjoern Schliessmann
> <[EMAIL PROTECTED]> said:
>
>> Marc 'BlackJack' Rintsch wrote:
>>
>>> No it doesn't -- look again at the example given above. It's
>>> legal syntax in Python but doesn't have the semantics implied by
>>> the example.
>> Sorry, I don't understand -- what is the difference between the
>> example as it is and the implied semantics of it?
>>
>> Regards,
>>
>>
>> Björn
>
> Yes, I'm not sure myself.
>
> In [1]: color = "red"
>
> In [2]: if color == "red" or "blue" or "green":
> ...: print 'Works.'
> ...:
> ...:
> Works.
>
> In [3]: if color == "blue" or "red" or "green":
> ...: print 'Works.'
> ...:
> ...:
> Works.
>
> In [4]: if not color == "blue" or "green":
> ...: print 'Works.'
> ...:
> ...:
> Works.
>
Try testing a little more completely:
>>> for color in ('blue', 'red', 'green', 'yellow'):
... if color == 'blue' or 'red' or 'green':
... print color, "compares true"
... else:
... print color, "compares false"
...
blue compares true
red compares true
green compares true
yellow compares true
>>>
Still think it works?
>>> print 'yellow' == 'blue' or 'red' or 'green'
red
>>> print 'blue' == 'blue' or 'red' or 'green'
True
>>>
Now do you understand why it doesn't work? Think "operator precedence".
regards
Steve
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