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Re: custom event in IE

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Michael Haufe (TNO) wrote:

> On Saturday, January 14, 2017 at 5:03:32 PM UTC-6, Scott Sauyet wrote:
>> `fn` cannot reasonably be used as a constructor function.
>> So are there any clear criteria to make clear that a function *can* be
>> used as a constructor?
> 
> That's where code-conventions come into play.
> 
> new Point(2,4)
> 
> vs.
> 
> new point(2,4)

Yes, but:

The fallacies here are to confuse native objects with host objects, and a 
straw man argument.  So apparently my killfile is working fine.  (To 
determine whether the second fallacy includes an affirmation of a consequent 
or a denial of an antecedent is left as an exercise to the reader.)

You *can* tell whether *this* *object* can be called as a constructor in the 
way that is specified.  There are two possibilities: either it throws an 
exception or it returns an unsuitable object.  There is no evidence to 
suggest that any host object called as a constructor would return an 
unsuitable object when that kind of call would be unsupported, and obviously 
there is evidence that several host objects, including *this* one, behave as 
described (i.e. not supporting to be called as a constructor with such an 
argument in the MSHTML DOM).  There is also a lot of evidence to suggest 
that a “typeof” test would be insufficient.

So it is unwise to test with “typeof”, and wise to use a try-catch statement 
with a more detailed investigation into the thrown exception here instead.

-- 
PointedEars
FAQ: <http://PointedEars.de/faq> | <http://PointedEars.de/es-matrix>
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custom event in IE Andrew Poulos <ap_prog@hotmail.com> - 2017-01-10 12:08 +1100
  Re: custom event in IE Andrew Poulos <ap_prog@hotmail.com> - 2017-01-10 12:20 +1100
    Re: custom event in IE Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2017-01-10 02:45 +0100
      Re: custom event in IE Andrew Poulos <ap_prog@hotmail.com> - 2017-01-10 15:32 +1100
        Re: custom event in IE Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2017-01-10 12:53 +0100
          Re: custom event in IE Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2017-01-11 08:25 +0100
        Re: custom event in IE James Kirk <noneya.invalid@gmail.com> - 2017-01-10 21:52 -0500
          Re: custom event in IE Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2017-01-11 04:09 +0100
            Re: custom event in IE James Kirk <noneya.invalid@gmail.com> - 2017-01-11 21:31 -0500
              Re: custom event in IE Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2017-01-12 14:22 +0100
            Re: custom event in IE Scott Sauyet <scott@sauyet.com> - 2017-01-14 23:01 +0000
              Re: custom event in IE "Michael Haufe (TNO)" <tno@thenewobjective.com> - 2017-01-15 09:51 -0800
                Re: custom event in IE Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2017-01-15 22:37 +0100
                Can we recognize Constructor Functions (was: custom event in IE) Scott Sauyet <scott@sauyet.com> - 2017-01-15 23:39 +0000
                Re: custom event in IE Scott Sauyet <scott@sauyet.com> - 2017-01-15 23:15 +0000
                Re: custom event in IE "Michael Haufe (TNO)" <tno@thenewobjective.com> - 2017-01-15 22:36 -0800
                Re: custom event in IE Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2017-01-16 12:54 +0100
                Re: custom event in IE "Michael Haufe (TNO)" <tno@thenewobjective.com> - 2017-01-16 14:18 -0800
                Re: custom event in IE Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2017-01-17 00:24 +0100

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