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Re: Inserting stuff received with AJAX into the DOM

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Cezary Tomczyk wrote:

> On 21/08/2017 16:44, Thomas 'PointedEars' Lahn wrote:
>> Cezary Tomczyk wrote:
>>> I am sure that:
>>>
>>> const par = document.createElement( 'p' );
>>>
>>> will always create HTML element. I can't see any real scenario where
>>> createElement method will return "something else than a reference to an
>>> object that has a method named “appendChild”" in that particular
>>> scenario.
>> 
>> Why?
> 
> https://developer.mozilla.org/en-US/docs/Web/API/Document/createElement
> […]

Certainly you can come up with something better than hearsay.
 
> In that particular case:
> 
> const par = document.createElement( 'p' );
> 
> this will return an HTML p element.

It may.
 
> As for "something else than a reference to an object that has a method
> named “appendChild”" may occur, of course, but this is a very rare case

When in doubt, be careful.

> I would say and even, if it'll occur then calling "appendChild" later
> will throw a DOM exception which I think it's good because it helps to
> catch the error on an early stage.

An exception, but not a “DOM exception” will be thrown, if the object does 
not have the method.  Or execution will simply stop with an error.  Who 
knows.  createElement() is a host object’s method.
 
> I just don't see a benefit of using "if" statement here instead of simple:
> 
> par.appendChild(text);

Defensive programming.

-- 
PointedEars
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Inserting stuff received with AJAX into the DOM bit-naughty@hotmail.com - 2017-08-19 12:35 -0700
  Re: Inserting stuff received with AJAX into the DOM bit-naughty@hotmail.com - 2017-08-19 12:55 -0700
    Re: Inserting stuff received with AJAX into the DOM Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2017-08-20 12:16 +0200
      Re: Inserting stuff received with AJAX into the DOM Cezary Tomczyk <cezary.tomczyk@gmail.com> - 2017-08-20 15:55 +0200
        Re: Inserting stuff received with AJAX into the DOM Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2017-08-20 19:18 +0200
          Re: Inserting stuff received with AJAX into the DOM Cezary Tomczyk <cezary.tomczyk@gmail.com> - 2017-08-20 21:50 +0200
            Re: Inserting stuff received with AJAX into the DOM Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2017-08-20 22:39 +0200
              Re: Inserting stuff received with AJAX into the DOM Cezary Tomczyk <cezary.tomczyk@gmail.com> - 2017-08-21 08:29 +0200
                Re: Inserting stuff received with AJAX into the DOM Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2017-08-21 16:44 +0200
                Re: Inserting stuff received with AJAX into the DOM Cezary Tomczyk <cezary.tomczyk@gmail.com> - 2017-08-21 17:24 +0200
                Re: Inserting stuff received with AJAX into the DOM Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2017-08-21 17:47 +0200
                Re: Inserting stuff received with AJAX into the DOM Cezary Tomczyk <cezary.tomczyk@gmail.com> - 2017-08-21 19:50 +0200
                Re: Inserting stuff received with AJAX into the DOM Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2017-08-21 22:16 +0200
                Re: Inserting stuff received with AJAX into the DOM Cezary Tomczyk <cezary.tomczyk@gmail.com> - 2017-08-26 09:25 +0200
                Re: Inserting stuff received with AJAX into the DOM Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2017-08-27 03:02 +0200
  Re: Inserting stuff received with AJAX into the DOM Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2017-08-20 12:30 +0200
  Re: Inserting stuff received with AJAX into the DOM bit-naughty@hotmail.com - 2017-08-20 07:37 -0700
    Re: Inserting stuff received with AJAX into the DOM "Evertjan." <exxjxw.hannivoort@inter.nl.net> - 2017-08-20 17:17 +0200
    Re: Inserting stuff received with AJAX into the DOM Tim Streater <timstreater@greenbee.net> - 2017-08-20 17:48 +0100
  Re: Inserting stuff received with AJAX into the DOM bit-naughty@hotmail.com - 2017-08-20 11:21 -0700
    Re: Inserting stuff received with AJAX into the DOM Tim Streater <timstreater@greenbee.net> - 2017-08-20 19:29 +0100
    Re: Inserting stuff received with AJAX into the DOM "Evertjan." <exxjxw.hannivoort@inter.nl.net> - 2017-08-21 01:29 +0200
      Re: Inserting stuff received with AJAX into the DOM Andrew Poulos <ap_prog@hotmail.com> - 2017-08-21 16:29 +1000
        Re: Inserting stuff received with AJAX into the DOM "Evertjan." <exxjxw.hannivoort@inter.nl.net> - 2017-08-21 12:25 +0200
        Re: Inserting stuff received with AJAX into the DOM Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2017-08-21 16:47 +0200

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