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

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jonas.thornvall@gmail.com wrote on 29 Sep 2015 in comp.lang.javascript:

> From what i understand an array, is a storage bin/stack of items. Now i
> have a stack of items that in most case do have an initiated element at
> index, but in some cases it is indeed empty. 

Wrong understanding!

There are NO empty elements.

Javascript arrays are infinite collections of pointers to variable storage,
where the pointers are identified by their positive integer index-values 

Only those elements that are defined exist.

var myArray = [];

is an empty array, 
but NONE of the elements are empty,
because there ARE NO elements [yet].

myArray.length is 0 here,
but is set to the highest defined element,
unless specifically set to a higher element.

var myArray = [];
alert(myArray.length); // 0

myArray[17] = 'b';
alert(myArray.length); // 18

myArray.length = 5555;
alert(myArray.length); // 5555

myArray.length = 2;
alert(myArray.length); // 2
alert(myArray[17]); // undefined

So myArray[17] is NOT empty, it does not EXIST anymore!

> Now i have a stack of items

Not so, a "stack" [in casu strictior] is a push-pull memory heap,
where ONLY the top-most element is ACCESSABLE,
and all elements below the top one are EXISTING.

Not so in a Javascript array.

[You could use an array for simulating a stack,
but that is another story.]


-- 
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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