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Re: why the ! operator can be used to determine a string is null?

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Ben Bacarisse wrote:

> "Evertjan." <exxjxw.hannivoort@inter.nl.net> writes:
>> Jon Ribbens <jon+usenet@unequivocal.eu> wrote on 09 Aug 2017 in
>> comp.lang.javascript:
>>> Unfortunately people tend to be very imprecise as to the meaning of
>>> the phrase "null string", and may variously mean either the actual
>>> null value or an empty string.
>>
>> Indeed,
>> a string is NEVER null,
>> because then it is NOT a string.

Correct regarding the `null` value in ECMAScript.
 
> Further complicated by the fact that there is a character called null
> (sometimes Null, Nul or NULL) so a string can "be null" in that it
> contains just that character.

As we are talking about ECMAScript, it is the Unicode character U+0000 NULL 
(to my surprise, not “NUL” as in US-ASCII) whose standard representation is 
a boxed “NUL” (AFAIK, it is *never* called “null”, “Null” or “Nul”):

<http://www.unicode.org/charts/PDF/U0000.pdf>

Otherwise, well spotted.  Different to C strings, for example, ECMAScript 
strings *can* contain that character without being automatically considered 
terminated (as the value is not used as a termination value).

-- 
PointedEars
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why the ! operator can be used to determine a string is null? Xue Feng <xf.lotus@yahoo.com> - 2017-08-08 23:43 +0800
  Re: why the ! operator can be used to determine a string is null? Robert Heller <heller@deepsoft.com> - 2017-08-08 11:16 -0500
  Re: why the ! operator can be used to determine a string is null? Jon Ribbens <jon+usenet@unequivocal.eu> - 2017-08-08 17:40 +0000
    Re: why the ! operator can be used to determine a string is null? Julio Di Egidio <julio@diegidio.name> - 2017-08-08 21:38 -0700
      Re: why the ! operator can be used to determine a string is null? John G Harris <niam@jghnorth.org.uk.invalid> - 2017-08-09 14:51 +0100
    Re: why the ! operator can be used to determine a string is null? Jon Ribbens <jon+usenet@unequivocal.eu> - 2017-08-09 11:01 +0000
      Re: why the ! operator can be used to determine a string is null? "Evertjan." <exxjxw.hannivoort@inter.nl.net> - 2017-08-09 16:17 +0200
        Re: why the ! operator can be used to determine a string is null? Ben Bacarisse <ben.usenet@bsb.me.uk> - 2017-08-09 16:14 +0100
          Re: why the ! operator can be used to determine a string is null? Julio Di Egidio <julio@diegidio.name> - 2017-08-09 10:25 -0700
            Re: why the ! operator can be used to determine a string is null? Ben Bacarisse <ben.usenet@bsb.me.uk> - 2017-08-09 21:04 +0100
              Re: why the ! operator can be used to determine a string is null? Julio Di Egidio <julio@diegidio.name> - 2017-08-09 13:11 -0700
                Re: why the ! operator can be used to determine a string is null? Ben Bacarisse <ben.usenet@bsb.me.uk> - 2017-08-10 00:59 +0100
                [ANN] Spam filter for Google Groups (was: why the ! operator can be used to determine a string is null?) Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2017-08-10 05:06 +0200
                Re: [ANN] Spam filter for Google Groups (was: why the ! operator can be used to determine a string is null?) Julio Di Egidio <julio@diegidio.name> - 2017-08-10 01:00 -0700
                Re: [ANN] Spam filter for Google Groups (was: why the ! operator can be used to determine a string is null?) John G Harris <niam@jghnorth.org.uk.invalid> - 2017-08-10 09:40 +0100
                Re: why the ! operator can be used to determine a string is null? Julio Di Egidio <julio@diegidio.name> - 2017-08-10 00:56 -0700
          Re: why the ! operator can be used to determine a string is null? "Evertjan." <exxjxw.hannivoort@inter.nl.net> - 2017-08-09 22:01 +0200
            Re: why the ! operator can be used to determine a string is null? Ben Bacarisse <ben.usenet@bsb.me.uk> - 2017-08-09 23:35 +0100
              Re: why the ! operator can be used to determine a string is null? "Evertjan." <exxjxw.hannivoort@inter.nl.net> - 2017-08-10 10:05 +0200
                Re: why the ! operator can be used to determine a string is null? Ben Bacarisse <ben.usenet@bsb.me.uk> - 2017-08-10 15:08 +0100
                Re: why the ! operator can be used to determine a string is null? "Evertjan." <exxjxw.hannivoort@inter.nl.net> - 2017-08-10 16:42 +0200
          Re: why the ! operator can be used to determine a string is null? Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2017-08-09 23:56 +0200
            Re: why the ! operator can be used to determine a string is null? Ben Bacarisse <ben.usenet@bsb.me.uk> - 2017-08-10 01:40 +0100
              Re: why the ! operator can be used to determine a string is null? Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2017-08-10 03:44 +0200
                Re: why the ! operator can be used to determine a string is null? Ben Bacarisse <ben.usenet@bsb.me.uk> - 2017-08-10 03:20 +0100
                Re: why the ! operator can be used to determine a string is null? Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2017-08-10 04:33 +0200
                Re: why the ! operator can be used to determine a string is null? Ben Bacarisse <ben.usenet@bsb.me.uk> - 2017-08-10 03:57 +0100
  Re: why the ! operator can be used to determine a string is null? Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2017-08-08 23:20 +0200
    Re: why the ! operator can be used to determine a string is null? Julio Di Egidio <julio@diegidio.name> - 2017-08-08 21:20 -0700
      Re: why the ! operator can be used to determine a string is null? Cezary Tomczyk <cezary.tomczyk@gmail.com> - 2017-08-09 09:26 +0200
        Re: why the ! operator can be used to determine a string is null? Julio Di Egidio <julio@diegidio.name> - 2017-08-09 01:31 -0700
        Re: why the ! operator can be used to determine a string is null? Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2017-08-09 11:32 +0200
          Re: why the ! operator can be used to determine a string is null? Cezary Tomczyk <cezary.tomczyk@gmail.com> - 2017-08-10 09:10 +0200
            Re: why the ! operator can be used to determine a string is null? Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2017-08-10 14:51 +0200
              Re: why the ! operator can be used to determine a string is null? Tim Streater <timstreater@greenbee.net> - 2017-08-10 15:11 +0100
              Re: why the ! operator can be used to determine a string is null? Cezary Tomczyk <cezary.tomczyk@gmail.com> - 2017-08-10 18:52 +0200

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