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Re: Eval of expr with 'or' and 'and' within

From Nick the Gr33k <support@superhost.gr>
Newsgroups comp.lang.python
Subject Re: Eval of expr with 'or' and 'and' within
Date 2013-06-14 18:16 +0300
Organization National Technical University of Athens, Greece
Message-ID <kpfc3k$1p7m$1@news.ntua.gr> (permalink)
References <kpep0v$spl$8@news.ntua.gr> <kpfai4$o0e$4@reader1.panix.com>

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On 14/6/2013 5:49 μμ, Grant Edwards wrote:
> On 2013-06-14, Nick the Gr33k <support@superhost.gr> wrote:
>
>> I started another thread
>
> no kidding.
>
>> because the last one was !@#$'ed up by irrelevant replies and was
>> difficult to jeep track.
>>
>>>>> name="abcd"
>>>>> month="efgh"
>>>>> year="ijkl"
>>
>>>>> print(name or month or year)
>> abcd
>>
>> Can understand that, it takes the first string out of the 3 strings
>> that has a truthy value.
>
> Yes, it does.  That's the way the language is defined to work.  If you
> don't like it, pick a different language.

I can understand OR stops at the first value when it finds it truthy, 
and doesn't care for the other expr parameters.

And that logical since we say:

(name or month or year)
is like saying:

print whatever of those 3 are True, at least 1 of them, if it doesn't 
not find any though for some reason it defaults to the last variable of 
the expression(another mystery for me)

the way i realize it is just that for this boolean evaluation of the 
expression to result in True if any of the above vars holds a truthy value.


Nice try, moving me to another newsgroup list :)

>>>>> print("k" in (name and month and year))
>> True
>>
>> No clue. since the expression in parenthesis returns 'abcd'
>
> No it doesn't.  Try it:
>
> Python 2.7.3 (default, Mar 20 2013, 14:16:24)
> [GCC 4.6.3] on linux2
> Type "help", "copyright", "credits" or "license" for more information.
>
>>>> name="abcd"
>>>> month="efgh"
>>>> year="ijkl"
>>>>
>>>> "k" in (name and month and year)
> True
>>>> (name and month and year)
> 'ijkl'
>>>>
>
>> how can 'k' contained within 'abcd' ?
Um sorry was a  typo.

I mean the expr eval results in the value of var year which is 'ijkl'.

 >>>> "k" in (name and month and year)
 > True

So yes it does.

My question is why the expr (name and month and year) result in the 
value of the last variable whic is variable year?

I cannot understand AND.

Isn't it like saying that:
(name and month and year)

all of these variables have to have truthy values so for the boolaean 
eval of the expr result in True?

-- 
What is now proved was at first only imagined!

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Thread

Eval of expr with 'or' and 'and' within Nick the Gr33k <support@superhost.gr> - 2013-06-14 12:50 +0300
  Re: Eval of expr with 'or' and 'and' within Fábio Santos <fabiosantosart@gmail.com> - 2013-06-14 11:03 +0100
  Re: Eval of expr with 'or' and 'and' within Robert Kern <robert.kern@gmail.com> - 2013-06-14 11:14 +0100
    Re: Eval of expr with 'or' and 'and' within Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2013-06-14 16:09 +0000
      Re: Eval of expr with 'or' and 'and' within rusi <rustompmody@gmail.com> - 2013-06-14 09:21 -0700
      Re: Eval of expr with 'or' and 'and' within Antoon Pardon <antoon.pardon@rece.vub.ac.be> - 2013-06-14 20:03 +0200
        Re: Eval of expr with 'or' and 'and' within rusi <rustompmody@gmail.com> - 2013-06-14 11:37 -0700
          Re: Eval of expr with 'or' and 'and' within Joshua Landau <joshua.landau.ws@gmail.com> - 2013-06-14 19:47 +0100
      Re: Eval of expr with 'or' and 'and' within alex23 <wuwei23@gmail.com> - 2013-06-14 23:50 -0700
        Re: Eval of expr with 'or' and 'and' within Nick the Gr33k <support@superhost.gr> - 2013-06-15 10:04 +0300
          Re: Eval of expr with 'or' and 'and' within Denis McMahon <denismfmcmahon@gmail.com> - 2013-06-15 07:49 +0000
            Re: Eval of expr with 'or' and 'and' within Nick the Gr33k <support@superhost.gr> - 2013-06-15 10:59 +0300
  Re: Eval of expr with 'or' and 'and' within Grant Edwards <invalid@invalid.invalid> - 2013-06-14 14:49 +0000
    Re: Eval of expr with 'or' and 'and' within Nick the Gr33k <support@superhost.gr> - 2013-06-14 18:16 +0300
      Re: Eval of expr with 'or' and 'and' within Nobody <nobody@nowhere.com> - 2013-06-14 17:42 +0100
        Re: Eval of expr with 'or' and 'and' within Grant Edwards <invalid@invalid.invalid> - 2013-06-14 19:30 +0000
          Re: Eval of expr with 'or' and 'and' within Nobody <nobody@nowhere.com> - 2013-06-15 00:02 +0100
        Re: Eval of expr with 'or' and 'and' within Nick the Gr33k <support@superhost.gr> - 2013-06-15 10:57 +0300
  Re: Eval of expr with 'or' and 'and' within Michael Torrie <torriem@gmail.com> - 2013-06-14 10:29 -0600
    Re: Eval of expr with 'or' and 'and' within Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2013-06-14 16:49 +0000
      Re: Eval of expr with 'or' and 'and' within Michael Torrie <torriem@gmail.com> - 2013-06-14 11:28 -0600
      Re: Eval of expr with 'or' and 'and' within MRAB <python@mrabarnett.plus.com> - 2013-06-14 18:49 +0100
      Re: Eval of expr with 'or' and 'and' within Chris Angelico <rosuav@gmail.com> - 2013-06-15 03:56 +1000
        Re: Eval of expr with 'or' and 'and' within Grant Edwards <invalid@invalid.invalid> - 2013-06-14 19:33 +0000
          Re: Eval of expr with 'or' and 'and' within Chris Angelico <rosuav@gmail.com> - 2013-06-15 09:56 +1000
        Re: Eval of expr with 'or' and 'and' within Nobody <nobody@nowhere.com> - 2013-06-15 00:09 +0100
          Re: Eval of expr with 'or' and 'and' within Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2013-06-15 01:34 +0000
            Re: Eval of expr with 'or' and 'and' within Cameron Simpson <cs@zip.com.au> - 2013-06-15 12:03 +1000
              NANs [was Re: Eval of expr with 'or' and 'and' within] Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2013-06-15 04:22 +0000
            Re: Eval of expr with 'or' and 'and' within Chris Angelico <rosuav@gmail.com> - 2013-06-15 12:21 +1000
      Re: Eval of expr with 'or' and 'and' within Nobody <nobody@nowhere.com> - 2013-06-15 00:06 +0100
        Re: Eval of expr with 'or' and 'and' within MRAB <python@mrabarnett.plus.com> - 2013-06-15 01:26 +0100
  Re: Eval of expr with 'or' and 'and' within Benjamin Kaplan <benjamin.kaplan@case.edu> - 2013-06-14 09:47 -0700
    Re: Eval of expr with 'or' and 'and' within Nick the Gr33k <support@superhost.gr> - 2013-06-14 20:01 +0300
      Re: Eval of expr with 'or' and 'and' within Robert Kern <robert.kern@gmail.com> - 2013-06-14 18:27 +0100
      Re: Eval of expr with 'or' and 'and' within Jussi Piitulainen <jpiitula@ling.helsinki.fi> - 2013-06-14 22:05 +0300
      Re: Eval of expr with 'or' and 'and' within Grant Edwards <invalid@invalid.invalid> - 2013-06-14 19:36 +0000
  Re: Eval of expr with 'or' and 'and' within Cameron Simpson <cs@zip.com.au> - 2013-06-15 10:14 +1000
    Re: Eval of expr with 'or' and 'and' within Nick the Gr33k <support@superhost.gr> - 2013-06-15 11:20 +0300
      Re: Eval of expr with 'or' and 'and' within Lele Gaifax <lele@metapensiero.it> - 2013-06-15 11:48 +0200
        Re: Eval of expr with 'or' and 'and' within Nick the Gr33k <support@superhost.gr> - 2013-06-15 16:24 +0300
        Re: Eval of expr with 'or' and 'and' within Nick the Gr33k <support@superhost.gr> - 2013-06-15 16:28 +0300

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