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Re: arr.push(obj);

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Christoph Michael Becker wrote:

> Thomas 'PointedEars' Lahn wrote:
>> Christoph Michael Becker wrote:
>>> I suggest to use ECMAScript Arrays the way they're meant to be used, and
>>> use indexes from 0 to n, and scale them as appropriate.
>> 
>> As long as the “length” property is not used directly, it can be useful
>> to have an *Array* instance with user-defined properties whose names are
>> string representations of negative numbers, positive numbers greater than
>> 2³² − 1, and non-integers.
> 
> While you're surely right that having "non negative" properties *can* be
> useful sometimes, it might often be confusing (particularly for
> beginners).

Non sequitur.  I expect people to use their brain while programming, IOW not 
to treat those special arrays as if they were ordinary arrays.

> Not only the length property will not work as "expected",

Depends on the implementation.  You are forgetting getters.

> but also several of the methods of Array.prototype, e.g. shift() and
> unshift(). 

You could override them.

> One does not have to use these, but than one could even use
> an object that does not "inherit" from Array at all.

But it makes sense to have an object that works like an Array in all other 
respects.  Many Array prototype methods are intentionally generic.

<http://PointedEars.de/es-matrix?filter=Array.prototype>

> Element access via the bracket notation as well as for loops will work on 
> such "arrays".

Depends on the implementation, see jsx.array.BigArray in 
<http://PointedEars.de/wsvn/JSX/trunk/array.js>.

I have written this to increase the upper border for indexes (from the 
getPrimes() discussion), and index < 0 gets you the same as in Python (with 
the bracket property accessor: only if Proxy is supported).

But now I am thinking of a property defining whether you can have negative 
indexes on the object, modifying that behavior slightly.  FWIW, the “length” 
property could then yield the difference between the maximum positive and 
the minimum negative index or just the maximum positive index + 1 as it 
always had; how did you get the idea that “for” loops would stop working for 
those objects *per se*?

> Quite fascinating! :)

Indeed.
 
-- 
PointedEars
FAQ: <http://PointedEars.de/faq> | SVN: <http://PointedEars.de/wsvn/>
Twitter: @PointedEars2 | ES Matrix: <http://PointedEars.de/es-matrix>
Please do not Cc: me. / Bitte keine Kopien per E-Mail.

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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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