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Re: Argument of the bool function

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candide wrote:
> About the standard function bool(), Python's official documentation 
> tells us the following :
>
> bool([x])
> Convert a value to a Boolean, using the standard truth testing procedure.
>
> In this context, what exactly a "value" is referring to ?
>
> For instance,
>  >>> x=42
>  >>> bool(x=5)
> True
>  >>>

Cute.  What's happening here is that `x=5` isn't really an expression. 
It's passing a value to the named parameter `x`, specified in the
definition of `bool`.  Try it with something else:

Python 2.6.5 (r265:79063, Apr 16 2010, 13:09:56) 
[GCC 4.4.3] on linux2
Type "help", "copyright", "credits" or "license" for more information.
>>> bool(y=5)
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
TypeError: 'y' is an invalid keyword argument for this function



Mel.

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Argument of the bool function candide <candide@free.invalid> - 2011-04-08 18:26 +0200
  Re: Argument of the bool function Benjamin Kaplan <benjamin.kaplan@case.edu> - 2011-04-08 12:41 -0400
    Re: Argument of the bool function candide <candide@free.invalid> - 2011-04-10 14:54 +0200
      Re: Argument of the bool function Chris Angelico <rosuav@gmail.com> - 2011-04-10 23:02 +1000
        Re: Argument of the bool function Mel <mwilson@the-wire.com> - 2011-04-10 12:21 -0400
          Re: Argument of the bool function "Colin J. Williams" <cjw@ncf.ca> - 2011-04-10 13:51 -0400
          Re: Argument of the bool function Ben Finney <ben+python@benfinney.id.au> - 2011-04-11 09:46 +1000
          Re: Argument of the bool function Ethan Furman <ethan@stoneleaf.us> - 2011-04-11 16:00 -0700
  Re: Argument of the bool function Mel <mwilson@the-wire.com> - 2011-04-08 16:42 +0000
  Re: Argument of the bool function Ian Kelly <ian.g.kelly@gmail.com> - 2011-04-08 10:43 -0600
    Re: Argument of the bool function candide <candide@free.invalid> - 2011-04-08 23:32 +0200
      Re: Argument of the bool function Ethan Furman <ethan@stoneleaf.us> - 2011-04-08 15:03 -0700
        Re: Argument of the bool function candide <candide@free.invalid> - 2011-04-09 00:59 +0200
          Re: Argument of the bool function Lie Ryan <lie.1296@gmail.com> - 2011-04-09 15:45 +1000
            Re: Argument of the bool function Grant Edwards <invalid@invalid.invalid> - 2011-04-10 03:35 +0000
              Re: Argument of the bool function rusi <rustompmody@gmail.com> - 2011-04-09 21:15 -0700
                Re: Argument of the bool function Robert Kern <robert.kern@gmail.com> - 2011-04-10 01:22 -0500
          Re: Argument of the bool function Robert Kern <robert.kern@gmail.com> - 2011-04-09 18:22 -0500
            Re: Argument of the bool function candide <candide@free.invalid> - 2011-04-10 02:33 +0200
      Re: Argument of the bool function Ben Finney <ben+python@benfinney.id.au> - 2011-04-09 07:57 +1000

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