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Re: How to manipulate integer that sometimes Nan and sometimes have a value?

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Tim Streater <timstreater@greenbee.net> wrote on 26 Sep 2015 in 
comp.lang.javascript:

> In article <XnsA521E8EF9A070eejj99@194.109.6.166>, Evertjan.
> <exxjxw.hannivoort@inter.nl.net> wrote:
> 
>>Tim Streater <timstreater@greenbee.net> wrote on 26 Sep 2015 in 
>>comp.lang.javascript:
>>
>>> In article <XnsA5219E7CBAC2eejj99@194.109.6.166>, Evertjan.
>>> <exxjxw.hannivoort@inter.nl.net> wrote:
>>> 
>>>>You should be glad that Javascript does not crash or error out,
>>>>but gives you the NaN-value, but it stays bad programming.
>>> 
>>> Personally I'd prefer if it were possible to have javascript give an
>>> exception when NaN is generated, for debugging purposes.
>>
>>if (isNaN(...)) Xception();
> 
> Very funny. So every time I'm about to modify a variable containing
> what ought be be a non-NaN value, and after every such computation, I
> need to check all variables for the NaN value, e.g.
> 
> if (isNaN(a)) Xception ();
> if (isNaN(b)) Xception ();

These two are not necessary, 
they will be automagically catched by the third. 

> c= a + b;
> if (isNaN(c)) Xception ();
> 
> and so on. That what you're saying ??

Yes, because Javascript is not a faith, 
that the user [you] can change to your desire.

You will have to do with what the different engine-builders 
rightly or wrongly did with the W3-concepts.  

Ofcourse you can submit your idea's,
but it will take perhaps 10 years for them to surface, if at all.

===================

However, you could build your own function,
perhaps something like:

function add(x,y) {
   var temp = x + y
   if (isNaN(temp)) Xception ();
   return temp;
};

===================

I would think it is not that difficult to KNOW,
that a and b are legitimate numbers,
unless they are user-input, 
in which case they would have to be pre-tested anyway.

The case posted by Jonas, that a NaN could appear unexpectedly from his own 
code, seems ludicrous to me. If you cannot trust your own code, better not 
write it, or think and build more modular.

-- 
Evertjan.
The Netherlands.
(Please change the x'es to dots in my emailaddress)

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How to manipulate integer that sometimes Nan and sometimes have a value? jonas.thornvall@gmail.com - 2015-09-25 07:31 -0700
  Re: How to manipulate integer that sometimes Nan and sometimes have a value? "Evertjan." <exxjxw.hannivoort@inter.nl.net> - 2015-09-25 17:09 +0200
    Re: How to manipulate integer that sometimes Nan and sometimes have a value? jonas.thornvall@gmail.com - 2015-09-25 14:43 -0700
      Re: How to manipulate integer that sometimes Nan and sometimes have a value? "Evertjan." <exxjxw.hannivoort@inter.nl.net> - 2015-09-26 08:54 +0200
    Re: How to manipulate integer that sometimes Nan and sometimes have a value? Erwin Moller <erwinmollerusenet@xs4all.nl> - 2015-09-30 15:04 +0200
      Re: How to manipulate integer that sometimes Nan and sometimes have a value? "Evertjan." <exxjxw.hannivoort@inter.nl.net> - 2015-09-30 21:13 +0200
        Re: How to manipulate integer that sometimes Nan and sometimes have a value? Erwin Moller <erwinmollerusenet@xs4all.nl> - 2015-10-01 10:44 +0200
          Re: How to manipulate integer that sometimes Nan and sometimes have a value? "Evertjan." <exxjxw.hannivoort@inter.nl.net> - 2015-10-01 13:56 +0200
            Re: How to manipulate integer that sometimes Nan and sometimes have a value? John Harris <niam@jghnorth.org.uk.invalid> - 2015-10-02 11:09 +0100
              Re: How to manipulate integer that sometimes Nan and sometimes have a value? Ben Bacarisse <ben.usenet@bsb.me.uk> - 2015-10-02 13:55 +0100
              Re: How to manipulate integer that sometimes Nan and sometimes have a value? "Evertjan." <exxjxw.hannivoort@inter.nl.net> - 2015-10-02 16:34 +0200
  Re: How to manipulate integer that sometimes Nan and sometimes have a value? Danny <dann90038@gmail.com> - 2015-09-25 15:11 -0700
    Re: How to manipulate integer that sometimes Nan and sometimes have a value? jonas.thornvall@gmail.com - 2015-09-25 17:50 -0700
      Re: How to manipulate integer that sometimes Nan and sometimes have a value? "Evertjan." <exxjxw.hannivoort@inter.nl.net> - 2015-09-26 08:59 +0200
        Re: How to manipulate integer that sometimes Nan and sometimes have a value? jonas.thornvall@gmail.com - 2015-09-26 04:25 -0700
          Re: How to manipulate integer that sometimes Nan and sometimes have a value? "Evertjan." <exxjxw.hannivoort@inter.nl.net> - 2015-09-26 15:00 +0200
            Re: How to manipulate integer that sometimes Nan and sometimes have a value? jonas.thornvall@gmail.com - 2015-09-26 06:15 -0700
              Re: How to manipulate integer that sometimes Nan and sometimes have a value? "Evertjan." <exxjxw.hannivoort@inter.nl.net> - 2015-09-26 15:34 +0200
                Re: How to manipulate integer that sometimes Nan and sometimes have a value? jonas.thornvall@gmail.com - 2015-09-26 08:06 -0700
                Re: How to manipulate integer that sometimes Nan and sometimes have a value? Tim Streater <timstreater@greenbee.net> - 2015-09-26 18:10 +0100
                Re: How to manipulate integer that sometimes Nan and sometimes have a value? "Evertjan." <exxjxw.hannivoort@inter.nl.net> - 2015-09-26 22:53 +0200
                Re: How to manipulate integer that sometimes Nan and sometimes have a value? Tim Streater <timstreater@greenbee.net> - 2015-09-26 22:37 +0100
                Re: How to manipulate integer that sometimes Nan and sometimes have a value? "Evertjan." <exxjxw.hannivoort@inter.nl.net> - 2015-09-27 10:05 +0200
                Re: How to manipulate integer that sometimes Nan and sometimes have a value? jonas.thornvall@gmail.com - 2015-09-27 08:42 -0700
                Re: How to manipulate integer that sometimes Nan and sometimes have a value? Tim Streater <timstreater@greenbee.net> - 2015-09-27 17:18 +0100
      Re: How to manipulate integer that sometimes Nan and sometimes have a value? Ben Bacarisse <ben.usenet@bsb.me.uk> - 2015-09-26 10:59 +0100
        Re: How to manipulate integer that sometimes Nan and sometimes have a value? "Evertjan." <exxjxw.hannivoort@inter.nl.net> - 2015-09-26 13:15 +0200
          Re: How to manipulate integer that sometimes Nan and sometimes have a value? Ben Bacarisse <ben.usenet@bsb.me.uk> - 2015-09-26 14:58 +0100
            Re: How to manipulate integer that sometimes Nan and sometimes have a value? "Evertjan." <exxjxw.hannivoort@inter.nl.net> - 2015-09-26 16:57 +0200
        Re: How to manipulate integer that sometimes Nan and sometimes have a value? jonas.thornvall@gmail.com - 2015-09-26 04:28 -0700
          Re: How to manipulate integer that sometimes Nan and sometimes have a value? "Evertjan." <exxjxw.hannivoort@inter.nl.net> - 2015-09-26 15:11 +0200
            Re: How to manipulate integer that sometimes Nan and sometimes have a value? Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2015-09-26 17:19 +0200
              Re: How to manipulate integer that sometimes Nan and sometimes have a value? "Evertjan." <exxjxw.hannivoort@inter.nl.net> - 2015-09-26 22:51 +0200
                Re: How to manipulate integer that sometimes Nan and sometimes have a value? Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2015-09-27 13:50 +0200
          Re: How to manipulate integer that sometimes Nan and sometimes have a value? Ben Bacarisse <ben.usenet@bsb.me.uk> - 2015-09-26 20:51 +0100
            Re: How to manipulate integer that sometimes Nan and sometimes have a value? jonas.thornvall@gmail.com - 2015-09-28 22:45 -0700
              Re: How to manipulate integer that sometimes Nan and sometimes have a value? "Evertjan." <exxjxw.hannivoort@inter.nl.net> - 2015-09-29 12:36 +0200
              Re: How to manipulate integer that sometimes Nan and sometimes have a value? Ben Bacarisse <ben.usenet@bsb.me.uk> - 2015-09-29 12:48 +0100
        Re: How to manipulate integer that sometimes Nan and sometimes have a value? Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2015-09-26 14:43 +0200
          Re: How to manipulate integer that sometimes Nan and sometimes have a value? jonas.thornvall@gmail.com - 2015-09-26 06:06 -0700
            Re: How to manipulate integer that sometimes Nan and sometimes have a value? John Harris <niam@jghnorth.org.uk.invalid> - 2015-09-27 14:06 +0100
              Re: How to manipulate integer that sometimes Nan and sometimes have a value? jonas.thornvall@gmail.com - 2015-09-27 08:50 -0700
              Re: How to manipulate integer that sometimes Nan and sometimes have a value? jonas.thornvall@gmail.com - 2015-09-27 08:53 -0700
                Re: How to manipulate integer that sometimes Nan and sometimes have a value? jonas.thornvall@gmail.com - 2015-09-27 09:02 -0700

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