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Re: Get inner text of HMTL element

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Thomas 'PointedEars' Lahn wrote:
> Cezary Tomczyk wrote:
[...]
>>>     function _isObject (a)
>>>     {
>>>       var t = typeof a;
>>>       return t == "function" || t == "object" && a !== null;
>>
>> How about using toString() to get the type of object?
>>
>> Object.prototype.toString.call(a).match(/\s([a-zA-Z]+)/)[1].toLowerCase()
>
> There is jsx.object.getClass() which does something similar (more efficient,

I'll take a look at above method.

> less error-prone), but it is not a good idea to use it here: the [[Class]]
> property of an ECMAScript value does not tell whether the value is a
> primitive value or a reference to an object, and with host objects all bets
> are off, even if one would be willing and able to invest the resources to
> keep the list up-to-date.

Thanks for explanation.

[...]
>> You probably referring to
>> http://robertnyman.com/2005/12/21/what-is-typeof-unknown/#comment-8001,
>> right?
>
> I would not refer to such nonsense.

Just one sentence doesn't explain what is behind "nonsense".

>>> last branch.  Anyhow, there is no guarantee that if some arbitrary
>>> element object has a “firstChild” or “nextSibling” property, the *target*
>>> element object also has it.
>>>
>>> Do you see now why it is a bad idea to infer from one property to
>>> another, even if the property names are the same and only the objects
>>> differ?
>>
>> Then what options do I have?
>>
>> 1. Check, if firstChild and nextSibling is available on
>> document.documentElement
>> or
>> 2. Check, if every element support firstChild and nextSibling?
>
> 3. Check if the *target* element supports “firstChild” and “nextSibling”.

Ok

> 4. Forget the whole idea.

Except point no. 3.

>>>>>>         get_inner_text = function(node) {
>>>>>>             var txt = '';
>>>>>>
>>>>>>             node = node.firstChild;
>>>>>>             while (node) {
>>>>>>                 if (node.nodeType === 3 || node.nodeType === 4) {
>>>>>
>>>>> I avoid strict comparison against property values of host objects.
>>>>> There are too many unknowns.
>>>>
>>>> I've never had problems with that, but I am not claim that there is no
>>>> problems. However, if you have a time then provide maybe some valuable
>>>> source where I can read about above problems. Otherwise, skip it, in
>>>> case of having no time.
>>>
>>> You are still operating in “Show me where it fails” mode in place of
>>> logic.
>>
>> But "There are too many unknowns." doesn't teach me why.
>
> There is no indication that an interface’s *attribute* MUST be implemented
> as a host object’s property using a *native* type or the *specified* type.
> However, if it is to be useful, it must be implemented so that it allows
> conversion to and from a native type.

Hm, I am lost at that point.

[...]
>>> No, same problem: The feature test does not happen on the target object
>>> because that object is not reliably accessible yet (if it even exists).
>>
>> So, the object itself must checked as well. It is in your above code,
>> right?
>
> You can and should skip the first *bogus* test, and do *only* the *reliable*
> test on the target object.  This comes at a price, though: if you cannot
> recognize the object (for example, through mapping), you will be forced to
> do the same test for each object when it is accessed.  AISB: Slower, but not
> as error-prone as your/DM’s “one-size-fits-all” initialization or whatever
> you/he call(s) it instead.

How reliable test on the target object may look in my case? Asking to 
understand more deeply.

>>>>> That aside, you should reconsider the actual probability that
>>>>> Node::textContent (DOM Level 3) would not be implemented but
>>>>> Document::createTreeWalker() (DOM Level 2 Traversal and Range) was.
>>>> Hm, maybe it is worth it to remove textContent and focus only on
>>>> createTreeWalker or normal recursive iteration? Less code to
>>>> maintenance.
>>> And much less efficient with regard to runtime and memory.  You should as
>>> yourself instead whether there is any actual *need* for tree-walking at
>>> this point.
>>
>> Well, looking at
>> https://developer.mozilla.org/en-US/docs/Web/API/Node.textContent looks
>> like textContent is supported by major browsers. If I will drop IE8
>> support then I can focus only on textContent, I think.
>
> Never believe blindly in anything you read; be sceptical and *verify* it.

Mostly I am doing in that way - verify it by myself.

-- 
Cezary Tomczyk
http://www.ctomczyk.pl/

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Thread

Get inner text of HMTL element Cezary Tomczyk <cezary.tomczyk@gmail.com> - 2014-02-22 18:21 +0100
  Re: Get inner text of HMTL element Martin Honnen <mahotrash@yahoo.de> - 2014-02-22 19:31 +0100
    Re: Get inner text of HMTL element Cezary Tomczyk <cezary.tomczyk@gmail.com> - 2014-02-22 20:51 +0100
      Re: Get inner text of HMTL element Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2014-02-22 21:11 +0100
        Re: Get inner text of HMTL element Cezary Tomczyk <cezary.tomczyk@gmail.com> - 2014-02-22 21:37 +0100
          Re: Get inner text of HMTL element Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2014-02-22 22:05 +0100
            Re: Get inner text of HMTL element Cezary Tomczyk <cezary.tomczyk@gmail.com> - 2014-02-22 23:38 +0100
              Re: Get inner text of HMTL element Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2014-02-23 10:43 +0100
                Re: Get inner text of HMTL element Cezary Tomczyk <cezary.tomczyk@gmail.com> - 2014-02-23 14:50 +0100
                Re: Get inner text of HMTL element Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2014-02-23 15:48 +0100
                Re: Get inner text of HMTL element Cezary Tomczyk <cezary.tomczyk@gmail.com> - 2014-02-24 21:01 +0100
                Re: Get inner text of HMTL element Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2014-02-24 22:34 +0100
                Re: Get inner text of HMTL element Cezary Tomczyk <cezary.tomczyk@gmail.com> - 2014-02-27 21:41 +0100
                Re: Get inner text of HMTL element Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2014-02-27 22:32 +0100
                Re: Get inner text of HMTL element Cezary Tomczyk <cezary.tomczyk@gmail.com> - 2014-02-28 13:44 +0100
                Re: Get inner text of HMTL element Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2014-02-28 16:54 +0100
                Re: Get inner text of HMTL element Cezary Tomczyk <cezary.tomczyk@gmail.com> - 2014-03-04 20:51 +0100
                Re: Get inner text of HMTL element ompalompasales2@gmail.com - 2014-03-04 12:59 -0800
  Re: Get inner text of HMTL element Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2014-02-22 20:59 +0100
    Re: Get inner text of HMTL element Cezary Tomczyk <cezary.tomczyk@gmail.com> - 2014-02-22 22:23 +0100
      Re: Get inner text of HMTL element Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2014-02-22 23:32 +0100
  Re: Get inner text of HMTL element Joao Rodrigues <groups_jr-1@yahoo.com.br> - 2014-02-22 21:27 -0300
    Re: Get inner text of HMTL element "se" <se@no-one.here> - 2014-02-23 05:35 +0100
      Re: Get inner text of HMTL element Joao Rodrigues <groups_jr-1@yahoo.com.br> - 2014-02-23 15:29 -0300
        Re: Get inner text of HMTL element "se" <se@no-one.here> - 2014-02-23 21:01 +0100
    Re: Get inner text of HMTL element Cezary Tomczyk <cezary.tomczyk@gmail.com> - 2014-02-23 20:02 +0100
      Re: Get inner text of HMTL element Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2014-02-23 21:55 +0100
        Re: Get inner text of HMTL element Cezary Tomczyk <cezary.tomczyk@gmail.com> - 2014-02-24 08:37 +0100
          Re: Get inner text of HMTL element Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2014-02-24 12:30 +0100
            Re: Get inner text of HMTL element Joao Rodrigues <groups_jr-1@yahoo.com.br> - 2014-02-24 15:09 -0300
              Re: Get inner text of HMTL element Christoph Michael Becker <cmbecker69@arcor.de> - 2014-02-24 19:43 +0100
                Re: Get inner text of HMTL element Joao Rodrigues <groups_jr-1@yahoo.com.br> - 2014-02-24 18:12 -0300
                Re: Get inner text of HMTL element Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2014-02-24 22:51 +0100
              Re: Get inner text of HMTL element Dr J R Stockton <reply1400@merlyn.demon.co.uk.invalid> - 2014-02-25 19:49 +0000
                Re: Get inner text of HMTL element Joao Rodrigues <groups_jr-1@yahoo.com.br> - 2014-02-26 05:20 -0300
                Re: Get inner text of HMTL element "se" <se@no-one.here> - 2014-02-26 17:10 +0100
                OT - Re: Get inner text of HMTL element Joao Rodrigues <groups_jr-1@yahoo.com.br> - 2014-02-26 15:48 -0300
                Re: OT - Re: Get inner text of HMTL element "Evertjan." <exxjxw.hannivoort@inter.nl.net> - 2014-02-26 22:43 +0100
                Re: OT - Re: Get inner text of HMTL element Dr J R Stockton <reply1400@merlyn.demon.co.uk.invalid> - 2014-02-27 15:00 +0000
                Re: OT - Re: Get inner text of HMTL element "Evertjan." <exxjxw.hannivoort@inter.nl.net> - 2014-02-28 10:50 +0100
                Re: OT - Re: Get inner text of HMTL element "se" <se@no-one.here> - 2014-02-27 10:57 +0100
                Re: Get inner text of HMTL element Dr J R Stockton <reply1400@merlyn.demon.co.uk.invalid> - 2014-02-27 15:46 +0000

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