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Re: Undefined variable

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Denis McMahon wrote:

> On Thu, 25 Apr 2013 22:05:46 +0200, M. Strobel wrote:
>> Am 25.04.2013 20:23, schrieb Denis McMahon:
>>> On Thu, 25 Apr 2013 10:10:24 +0200, M. Strobel wrote:
>>>> I propose a new reading of "PHP Notice: undefined variable...", it
>>>> goes:
>>>>
>>>>    Hey, you are using a variable that is not defined. I will put a
>>>>    null
>>> ..........................................................^^^^
>>> 
>>> *might*
>>> 
>>>>    into it.
>>>>    Because I will make it easy for you.
>>>>    If you don't care I won't either.
>>> 
>>> + some lines:
>>>      I may put some random value there instead.
>>>      The double I use now might not be the string I use next.
>>>      Or the integer I used last.
>>> […]     
> […]
> 
> I did wonder about:
> 
> "The array of doubles I'm using now might not be the class of kitten
> hugging monkeys I'll use next week or the tuples of solar hydrogen I used
> yesterday."
> 
> but that seemed perhaps a little too complex for some of the readers
> here. :)
> 
> (although the kitten hugging monkeys may be more intelligent than some of
> those readers too ... and come to that, so might the tuples of solar
> hydrogen)

However, the non-trolling reader will observe that the evaluation value of a 
reference to an undefined variable actually *is* NULL, and that type 
juggling as it occurs e.g. with the “==” operator or a type-converting test 
(as opposed to with “===”) is *well-defined* (albeit perhaps unintuitive to 
some), in PHP (and other dynamically typed programming languages).

It is simply false that a replacement value will be chosen randomly.

<http://www.php.net/manual/en/language.variables.basics.php>
<http://www.php.net/manual/en/language.types.type-juggling.php>


PointedEars
-- 
Sometimes, what you learn is wrong. If those wrong ideas are close to the 
root of the knowledge tree you build on a particular subject, pruning the 
bad branches can sometimes cause the whole tree to collapse.
  -- Mike Duffy in cljs, <news:Xns9FB6521286DB8invalidcom@94.75.214.39>

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Undefined variable Question Boy <question.boy@hotmail.com> - 2013-04-23 19:16 -0700
  Re: Undefined variable Question Boy <question.boy@hotmail.com> - 2013-04-23 20:06 -0700
  Re: Undefined variable Richard Yates <richard@yatesguitar.com> - 2013-04-23 20:08 -0700
    Re: Undefined variable Question Boy <question.boy@hotmail.com> - 2013-04-23 20:27 -0700
      Re: Undefined variable Question Boy <question.boy@hotmail.com> - 2013-04-23 20:49 -0700
        Re: Undefined variable David Robley <me@home.invalid> - 2013-04-24 17:34 +0930
        Re: Undefined variable Jerry Stuckle <jstucklex@attglobal.net> - 2013-04-24 05:53 -0400
        Re: Undefined variable Chuck Anderson <cycletourist@invalid.invalid> - 2013-04-24 14:02 -0600
          Re: Undefined variable Jerry Stuckle <jstucklex@attglobal.net> - 2013-04-24 22:23 -0400
            Re: Undefined variable Jerry Stuckle <jstucklex@attglobal.net> - 2013-04-24 22:24 -0400
              Re: Undefined variable Tim Streater <timstreater@greenbee.net> - 2013-04-25 08:36 +0100
                Re: Undefined variable Jerry Stuckle <jstucklex@attglobal.net> - 2013-04-25 05:13 -0400
                Re: Undefined variable Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2013-04-25 14:04 +0200
                Re: Undefined variable The Natural Philosopher <tnp@invalid.invalid> - 2013-04-25 13:12 +0100
            Re: Undefined variable Chuck Anderson <cycletourist@invalid.invalid> - 2013-04-25 01:03 -0600
              Re: Undefined variable Jerry Stuckle <jstucklex@attglobal.net> - 2013-04-25 05:22 -0400
                Re: Undefined variable Chuck Anderson <cycletourist@invalid.invalid> - 2013-04-25 23:59 -0600
      Re: Undefined variable The Natural Philosopher <tnp@invalid.invalid> - 2013-04-24 10:24 +0100
        Re: Undefined variable Jerry Stuckle <jstucklex@attglobal.net> - 2013-04-24 05:55 -0400
  Re: Undefined variable Christoph Becker <cmbecker69@gmx.de> - 2013-04-24 12:20 +0200
    Re: Undefined variable Question Boy <question.boy@hotmail.com> - 2013-04-24 06:51 -0700
      Re: Undefined variable "M. Strobel" <sorry_no_mail_here@nowhere.dee> - 2013-04-25 10:10 +0200
        Re: Undefined variable Denis McMahon <denismfmcmahon@gmail.com> - 2013-04-25 18:23 +0000
          Re: Undefined variable "M. Strobel" <sorry_no_mail_here@nowhere.dee> - 2013-04-25 22:05 +0200
            Re: Undefined variable Denis McMahon <denismfmcmahon@gmail.com> - 2013-04-26 03:27 +0000
              Re: Undefined variable Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2013-04-26 21:30 +0200

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