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Re: arr.push(obj);

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jonas.thornvall@gmail.com wrote on 11 mrt 2014 in comp.lang.javascript:

>> That is impossible. Arrays have no negative indexes, see above.
> Well i showed you it can be done, was i just lucky??????

No it cannot be done and [so] you did not show me.

You are just extremely unlucky not comprehending this yet.

The thing we call an index of an array can only be a non negative integer.

All kind of array-functions expect of an array where the elements have 
numeric order within these confines.

for instance, how would you reverse a group of elements with no order,
or join them sequencially without order?

============== some array functions =========================
length  returns the highest index + 1

join()  joins all elements of an array into a string

lastIndexOf()	 searches the array for an element, starting at the end, 
       and returns its position

pop()  Removes the last element of an array, and returns that element

push() Adds new elements to the end of an array, 
       and returns the new length

reverse()  Reverses the order of the elements in an array

shift()  Removes the first element of an array, and returns that element

slice()  Selects a part of an array, and returns the new array

splice()  Adds/Removes elements from an array

unshift()  Adds new elements to the beginning of an array, 
           and returns the new length
========================================

Now an object can have keys, they are NOT called indexes:

var obj = {};

obj[1]
obj[-1]
obj[-7.555]
obj['foo']

but you cannot use any of the above functions,
as long as it is not an array too, 
defined with

var obj = [];

and even then obj[1] will be the only array element,
so obj.length will be 2.

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

Synopsis:

An array is not the same as an object.

The elements of an array are indicated by their index.
An array cannot have other indexes than non-negative integers.
The elements of an array have order.
This order makes most of the above functions possible.

An object's elements are indicated by a key,
this can be any string or even a number the probably will be converted to a 
string.
The elements of an object have no order.

However an array is also an object, so can have elements indicated by an 
index, and additionally elements that are indicated by keys.

An object not defined as an array is not an array.

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

Do you still hold that an array can have negative index values?


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

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arr.push(obj); jonas.thornvall@gmail.com - 2014-03-10 17:38 -0700
  Re: arr.push(obj); jonas.thornvall@gmail.com - 2014-03-10 20:19 -0700
    Re: arr.push(obj); jonas.thornvall@gmail.com - 2014-03-10 20:28 -0700
      Re: arr.push(obj); jonas.thornvall@gmail.com - 2014-03-10 21:19 -0700
        Re: arr.push(obj); Joao Rodrigues <groups_jr-1@yahoo.com.br> - 2014-03-11 06:59 -0300
          Re: arr.push(obj); Christoph Michael Becker <cmbecker69@arcor.de> - 2014-03-11 16:02 +0100
            Re: arr.push(obj); Ben Bacarisse <ben.usenet@bsb.me.uk> - 2014-03-11 16:22 +0000
            Re: arr.push(obj); Joao Rodrigues <groups_jr-1@yahoo.com.br> - 2014-03-11 13:32 -0300
  Re: arr.push(obj); "Evertjan." <exxjxw.hannivoort@inter.nl.net> - 2014-03-11 10:21 +0100
    Re: arr.push(obj); jonas.thornvall@gmail.com - 2014-03-11 03:53 -0700
      Re: arr.push(obj); "Evertjan." <exxjxw.hannivoort@inter.nl.net> - 2014-03-11 14:03 +0100
        Re: arr.push(obj); jonas.thornvall@gmail.com - 2014-03-11 07:45 -0700
          Re: arr.push(obj); "Evertjan." <exxjxw.hannivoort@inter.nl.net> - 2014-03-11 16:24 +0100
            Re: arr.push(obj); jonas.thornvall@gmail.com - 2014-03-11 10:40 -0700
              Re: arr.push(obj); jonas.thornvall@gmail.com - 2014-03-11 10:51 -0700
                Re: arr.push(obj); Christoph Michael Becker <cmbecker69@arcor.de> - 2014-03-11 19:23 +0100
                Re: arr.push(obj); jonas.thornvall@gmail.com - 2014-03-11 15:33 -0700
                Re: arr.push(obj); "Evertjan." <exxjxw.hannivoort@inter.nl.net> - 2014-03-12 00:37 +0100
                Re: arr.push(obj); jonas.thornvall@gmail.com - 2014-03-11 16:46 -0700
                Re: arr.push(obj); "Evertjan." <exxjxw.hannivoort@inter.nl.net> - 2014-03-12 01:05 +0100
                Re: arr.push(obj); Christoph Michael Becker <cmbecker69@arcor.de> - 2014-03-12 01:40 +0100
                Re: arr.push(obj); Christoph Michael Becker <cmbecker69@arcor.de> - 2014-03-12 00:48 +0100
                Re: arr.push(obj); jonas.thornvall@gmail.com - 2014-03-11 15:43 -0700
                Re: arr.push(obj); jonas.thornvall@gmail.com - 2014-03-11 16:18 -0700
                Re: arr.push(obj); "Evertjan." <exxjxw.hannivoort@inter.nl.net> - 2014-03-12 00:39 +0100
                Re: arr.push(obj); Christoph Michael Becker <cmbecker69@arcor.de> - 2014-03-12 00:52 +0100
                Re: arr.push(obj); Christoph Michael Becker <cmbecker69@arcor.de> - 2014-03-12 00:49 +0100
                Re: arr.push(obj); jonas.thornvall@gmail.com - 2014-03-11 17:16 -0700
                Re: arr.push(obj); Christoph Michael Becker <cmbecker69@arcor.de> - 2014-03-12 02:07 +0100
                Re: arr.push(obj); jonas.thornvall@gmail.com - 2014-03-11 18:13 -0700
                Re: arr.push(obj); Christoph Michael Becker <cmbecker69@arcor.de> - 2014-03-13 02:25 +0100
                Re: arr.push(obj); Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2014-03-13 11:03 +0100
                Re: arr.push(obj); jonas.thornvall@gmail.com - 2014-03-12 07:46 -0700
                Re: arr.push(obj); Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2014-03-12 01:27 +0100
                Re: arr.push(obj); Christoph Michael Becker <cmbecker69@arcor.de> - 2014-03-12 01:44 +0100
          Re: arr.push(obj); Christoph Michael Becker <cmbecker69@arcor.de> - 2014-03-11 16:26 +0100
            Re: arr.push(obj); Carlos Pedro <carlospedr@gmail.com> - 2014-03-11 09:21 -0700
            Re: arr.push(obj); Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2014-03-11 18:01 +0100
              Re: arr.push(obj); Christoph Michael Becker <cmbecker69@arcor.de> - 2014-03-11 19:15 +0100
                Re: arr.push(obj); Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2014-03-11 20:32 +0100
                Re: arr.push(obj); Christoph Michael Becker <cmbecker69@arcor.de> - 2014-03-12 01:01 +0100
                Re: arr.push(obj); Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2014-03-12 04:08 +0100
                Re: arr.push(obj); Christoph Michael Becker <cmbecker69@arcor.de> - 2014-03-12 18:00 +0100
  Re: arr.push(obj); Joao Rodrigues <groups_jr-1@yahoo.com.br> - 2014-03-11 06:24 -0300
    Re: arr.push(obj); jonas.thornvall@gmail.com - 2014-03-11 03:47 -0700
      Re: arr.push(obj); Ben Bacarisse <ben.usenet@bsb.me.uk> - 2014-03-11 15:19 +0000

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