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Boolean confusion

John Roth newsgroups at jhrothjr.com
Fri Oct 31 14:19:26 EST 2003 
"Frantisek Fuka" <fuka at fuxoft.cz> wrote in message
news:bnua52$tnv$1 at ns.felk.cvut.cz...
> Can anyone please explain why these two give different results in Python
> 2.3?
>
>  >>> 'a' in 'abc' == 1
> False
>  >>> ('a' in 'abc') == 1
> True
>
> I know it's not a good idea to compare boolean with Integer but that's
> not the answer to my question.

According to the operator precedence table given in the
Python Reference Manual, section 5.14 (2.2.3 version)
the "==" operator has higher precidence (that is, it will
be evaluated first) than the "in" operator. The table is,
unfortunately, upside down from my perspective, but
a close examination of the explanation shows what is
happening.

In other words, your first expression is equivalent
to:

"a" in ("abc" == 1)

John Roth
>
> -- 
>                                           Frantisek Fuka
> (yes, that IS my real name)
> (and it's pronounced "Fran-tjee-shek Foo-kah")
> ----------------------------------------------------
> My E-mail:   fuka at fuxoft.cz
> My Homepage: http://www.fuxoft.cz
> My ICQ:      2745855
>
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