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Re: Changing styles values by Element Name

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Evertjan. wrote:

> Scott Johnson wrote on 06 jun 2012 in comp.lang.javascript:
>> On 6/5/2012 1:26 PM, Jeremy J Starcher wrote:
>>> On Sun, 03 Jun 2012 09:22:18 -0700, Scott Johnson wrote:
>>>> On 6/3/2012 8:44 AM, Evertjan. wrote:
>>>>> Martin Honnen wrote on 03 jun 2012 in comp.lang.javascript:
>>>> Ahhh now I see.
>>>>
>>>> getElementsByName returns an array of (duh) elements. I guess the (s)
>>>> should of clued me in.
>>>
>>> Actually, it returns at HTMLCollection which is array-like.  The
>>> difference may seem subtle, but confusing the two can cause bugs or
>>> runtime errors.
>>>
>>> https://developer.mozilla.org/en/DOM/HTMLCollection
>> 
>> Thanks for the extra info and link.  Valuable info.
> 
> All js-variables are valuable, even with "undefined".

You misunderstand.  Scott thanked Jeremy for the information he provided to 
him – that getElementsByName() only returns a (reference to) an array-*like* 
object which implements the HTMLCollection interface.  He considered that 
information valuable.

However actually, the method is *specified* to return a reference to an 
object implementing the *NodeList* interface instead:

[1] <http://www.w3.org/TR/DOM-Level-2-HTML/html.html#ID-71555259>
[2] <http://www.whatwg.org/specs/web-apps/current-
work/multipage/dom.html#dom-document-getelementsbyname>

It is a specialty of the Gecko DOM that the referred object also implements 
the HTMLCollection interface:

<https://developer.mozilla.org/en/DOM/document.getElementsByName>
(refers to both the specifications above)

This can be proven by showing that in Iceweasel (Firefox) 10.0.5 the 
referred object inherits a namedItem() method, which is native to 
HTMLCollection and HTMLOptionsCollection implementations only [1].

I do not understand to what end that is in the Gecko DOM, as the namedItem() 
method of the referred object, when called with the name as argument can 
reasonably at most only return the same value that the item() method returns 
when called with argument 0 (to yield the first item of the NodeList) [1].

> All[?] DOM collections can be actively used in JS,

No, it depends on the runtime environment of the ECMAScript implementation 
that provides the DOM implementation whether and which DOM collections can 
be used.

> except the garbage collection.

You are not making sense.  Garbage collection is a functionality of the 
ECMAScript implementation; it is not a DOM collection.


PointedEars
-- 
var bugRiddenCrashPronePieceOfJunk = (
    navigator.userAgent.indexOf('MSIE 5') != -1
    && navigator.userAgent.indexOf('Mac') != -1
)  // Plone, register_function.js:16

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Changing styles values by Element Name Scott Johnson <noonehome@chalupasworld.com> - 2012-06-03 06:46 -0700
  Re: Changing styles values by Element Name Martin Honnen <mahotrash@yahoo.de> - 2012-06-03 15:53 +0200
    Re: Changing styles values by Element Name "Evertjan." <exjxw.hannivoort@interxnl.net> - 2012-06-03 15:44 +0000
      Re: Changing styles values by Element Name Scott Johnson <noonehome@chalupasworld.com> - 2012-06-03 09:06 -0700
      Re: Changing styles values by Element Name Scott Johnson <noonehome@chalupasworld.com> - 2012-06-03 09:22 -0700
        Re: Changing styles values by Element Name Jeremy J Starcher <r3jjs@yahoo.com> - 2012-06-05 20:26 +0000
          Re: Changing styles values by Element Name Scott Johnson <noonehome@chalupasworld.com> - 2012-06-05 20:52 -0700
            Re: Changing styles values by Element Name "Evertjan." <exxjxw.hannivoort@inter.nl.net> - 2012-06-06 09:57 +0000
              Re: Changing styles values by Element Name Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2012-06-09 11:43 +0200
                Re: Changing styles values by Element Name Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2012-06-09 13:03 +0200
                Re: Changing styles values by Element Name "Evertjan." <exxjxw.hannivoort@inter.nl.net> - 2012-06-09 14:14 +0000
                Re: Changing styles values by Element Name Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2012-06-09 18:13 +0200
                Re: Changing styles values by Element Name Luuk <luuk@invalid.lan> - 2012-06-09 18:35 +0200
                Re: Changing styles values by Element Name "Evertjan." <exxjxw.hannivoort@inter.nl.net> - 2012-06-10 10:33 +0000
                Re: Changing styles values by Element Name Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2012-06-10 14:50 +0200
  Re: Changing styles values by Element Name SAM <stephanemoriaux.NoAdmin@wanadoo.fr.invalid> - 2012-06-04 15:32 +0200

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