Paul Rubin wrote:
> Steve Holden <[EMAIL PROTECTED]> writes:
>
>>The really interesting question your post raises, though, is "Why do
>>you feel it's necessary to test to see whether a variable is a
>>Boolean?".
>
>
> What's the point of having Booleans, if you can't tell them from integers?
Booleans are specifically defined as a subtype of int at the C level.
One might also ask "what's the point of having floats if you can't tell
them from integers":
>>> 0.0 in [1,2,0,4]
True
>>>
It just so happens that __contains__() uses an equality test (which it
should) and equality tests perform certain coercions (which they
arguably shouldn't, but in that case I wouldn't be the one doing the
arguing).
"""
The only thing that changes is the preferred values to represent
truth values when returned or assigned explicitly. Previously,
these preferred truth values were 0 and 1; the PEP changes the
preferred values to False and True, and changes built-in
operations to return these preferred values.
"""
PEP 285.
regards
Steve
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