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Re: Give alert if form checkbox array is empty

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Stefan Weiss wrote:

> On 01/21/2016 00:59, Thomas 'PointedEars' Lahn wrote:
>> You should familiarize yourself with the Array methods introduced with
>> implementations of ECMAScript Edition 5 at the latest, in order to not
>> write explicit loops where they are not necessary.  Examples have been
>> given.
>> 
>> Keep in mind that the built-in implementation of an algorithm is
>> naturally always the most efficient one to use as it is, at best,
>> provided in machine code already.
> 
> Had you tested this, you would have discovered that your version - the
> one with `[].slice.call(...)` - takes 2 to 17 times longer than the
> simple loop, depending on the browser and which checkboxes are checked.

Irrelevant argument as that was _not_ what I as referring to.  Besides, you 
are deliberately ignoring compilation here, but considering it elsewhere.
 
> Also, storing `subjectTypes.length` in a variable has almost no benefit:
> it makes the loop a tiny bit faster in Firefox (about 5 nanoseconds per
> iteration on my laptop), and a tiny bit slower in Chrome (about the same
> difference in the other direction). Making assumptions about the
> performance of modern JS engines without testing or intimate knowledge
> of the internal optimizations is pointless.

It has been shown in this newsgroup to be much more efficient in general.  
Your test methodology is flawed.

> Not that speed matters in this case - there are four checkboxes to test,
> what kind of performance do you think we need for that? But you were
> criticizing posted code for its performance and at the same time
> advocating a slower and less readable version, so I thought you'd like
> to know.

Your logic is flawed, too.

-- 
PointedEars
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Thread

Give alert if form checkbox array is empty Bunyip <bunyip@koalanet.com.au> - 2016-01-20 13:28 +1000
  Re: Give alert if form checkbox array is empty JJ <jj4public@vfemail.net> - 2016-01-20 12:30 +0700
    Re: Give alert if form checkbox array is empty Bunyip <bunyip@koalanet.com.au> - 2016-01-20 17:55 +1000
      Re: Give alert if form checkbox array is empty JJ <jj4public@vfemail.net> - 2016-01-20 19:29 +0700
        Re: Give alert if form checkbox array is empty "Evertjan." <exxjxw.hannivoort@inter.nl.net> - 2016-01-20 13:46 +0100
  Re: Give alert if form checkbox array is empty Cezary Tomczyk <cezary.tomczyk@gmail.com> - 2016-01-20 08:23 +0000
    Re: Give alert if form checkbox array is empty Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2016-01-20 15:52 +0100
      Re: Give alert if form checkbox array is empty Cezary Tomczyk <cezary.tomczyk@gmail.com> - 2016-01-20 15:43 +0000
        Re: Give alert if form checkbox array is empty Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2016-01-20 17:15 +0100
          Re: Give alert if form checkbox array is empty Jon Ribbens <jon+usenet@unequivocal.co.uk> - 2016-01-20 17:53 +0000
            Re: Give alert if form checkbox array is empty Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2016-01-20 20:39 +0100
              Re: Give alert if form checkbox array is empty Jon Ribbens <jon+usenet@unequivocal.co.uk> - 2016-01-20 22:46 +0000
          Re: Give alert if form checkbox array is empty Cezary Tomczyk <cezary.tomczyk@gmail.com> - 2016-01-21 07:53 +0000
            Re: Give alert if form checkbox array is empty Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2016-01-21 10:52 +0100
              Re: Give alert if form checkbox array is empty Cezary Tomczyk <cezary.tomczyk@gmail.com> - 2016-01-21 10:26 +0000
                Re: Give alert if form checkbox array is empty Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2016-01-22 00:07 +0100
  Re: Give alert if form checkbox array is empty Stefan Weiss <krewecherl@gmail.com> - 2016-01-20 10:28 +0100
    Re: Give alert if form checkbox array is empty Bunyip <bunyip@koalanet.com.au> - 2016-01-21 08:05 +1000
      Re: Give alert if form checkbox array is empty Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2016-01-21 00:59 +0100
        Re: Give alert if form checkbox array is empty Stefan Weiss <krewecherl@gmail.com> - 2016-01-21 03:17 +0100
          Re: Give alert if form checkbox array is empty Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2016-01-21 08:54 +0100
            Re: Give alert if form checkbox array is empty Stefan Weiss <krewecherl@gmail.com> - 2016-01-21 12:17 +0100
        Re: Give alert if form checkbox array is empty John Harris <niam@jghnorth.org.uk.invalid> - 2016-01-21 14:16 +0000
        Re: Give alert if form checkbox array is empty Scott Sauyet <scott.sauyet@gmail.com> - 2016-01-21 19:52 -0800
          Re: Give alert if form checkbox array is empty Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2016-01-22 09:48 +0100
            Re: Give alert if form checkbox array is empty Scott Sauyet <scott.sauyet@gmail.com> - 2016-01-22 10:45 -0800
              Re: Give alert if form checkbox array is empty Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2016-01-23 19:41 +0100
                Re: Give alert if form checkbox array is empty Scott Sauyet <scott.sauyet@gmail.com> - 2016-01-24 17:51 -0800
                Re: Give alert if form checkbox array is empty Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2016-01-25 19:46 +0100
                Re: Give alert if form checkbox array is empty Scott Sauyet <scott.sauyet@gmail.com> - 2016-01-27 11:09 -0800
        Re: Give alert if form checkbox array is empty Dr J R Stockton <reply1600@merlyn.demon.co.uk.invalid> - 2016-01-23 22:22 +0000
        Re: Give alert if form checkbox array is empty Scott Sauyet <scott.sauyet@gmail.com> - 2016-01-27 11:06 -0800
          Re: Give alert if form checkbox array is empty Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2016-01-28 14:46 +0100
            Re: Give alert if form checkbox array is empty Gene Wirchenko <genew@telus.net> - 2016-01-28 10:30 -0800
              Re: Give alert if form checkbox array is empty Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2016-01-28 20:06 +0100
                Re: Give alert if form checkbox array is empty Scott Sauyet <scott.sauyet@gmail.com> - 2016-01-28 23:32 -0800
                Re: Give alert if form checkbox array is empty "Evertjan." <exxjxw.hannivoort@inter.nl.net> - 2016-01-29 09:05 +0100
                Re: Give alert if form checkbox array is empty Scott Sauyet <scott.sauyet@gmail.com> - 2016-01-29 06:02 -0800
                Re: Give alert if form checkbox array is empty Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2016-01-29 20:54 +0100
                Re: Give alert if form checkbox array is empty John Harris <niam@jghnorth.org.uk.invalid> - 2016-01-29 10:36 +0000
                Re: Give alert if form checkbox array is empty Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2016-02-09 04:39 +0100
                Re: Give alert if form checkbox array is empty John Harris <niam@jghnorth.org.uk.invalid> - 2016-02-09 18:07 +0000
                Re: Give alert if form checkbox array is empty Gene Wirchenko <genew@telus.net> - 2016-01-29 09:32 -0800
                Re: Give alert if form checkbox array is empty Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2016-01-29 20:34 +0100
                Re: Give alert if form checkbox array is empty Aleksandro <aleksandro@gmx.com> - 2016-01-29 16:50 -0300
                Re: Give alert if form checkbox array is empty Stefan Weiss <krewecherl@gmail.com> - 2016-01-30 03:31 +0100
                Re: Give alert if form checkbox array is empty Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2016-01-30 04:19 +0100
                Re: Give alert if form checkbox array is empty Stefan Weiss <krewecherl@gmail.com> - 2016-01-30 05:01 +0100
              Re: Give alert if form checkbox array is empty Aleksandro <aleksandro@gmx.com> - 2016-01-28 16:39 -0300
            Re: Give alert if form checkbox array is empty Scott Sauyet <scott.sauyet@gmail.com> - 2016-01-29 06:04 -0800
              Re: Give alert if form checkbox array is empty Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2016-01-29 20:54 +0100
                Re: Give alert if form checkbox array is empty Scott Sauyet <scott.sauyet@gmail.com> - 2016-01-29 14:55 -0800
                Re: Give alert if form checkbox array is empty Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2016-01-30 04:55 +0100
                Re: Give alert if form checkbox array is empty Scott Sauyet <scott.sauyet@gmail.com> - 2016-01-30 15:48 -0800
                Re: Give alert if form checkbox array is empty Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2016-01-31 21:02 +0100
                Re: Give alert if form checkbox array is empty Scott Sauyet <scott.sauyet@gmail.com> - 2016-01-31 13:08 -0800
                Re: Give alert if form checkbox array is empty Andrew Poulos <ap_prog@hotmail.com> - 2016-02-01 12:28 +1100
                Re: Give alert if form checkbox array is empty Scott Sauyet <scott.sauyet@gmail.com> - 2016-02-01 17:58 -0800
  Re: Give alert if form checkbox array is empty "Michael Haufe (TNO)" <tno@thenewobjective.com> - 2016-01-20 06:25 -0800
  Re: Give alert if form checkbox array is empty Aleksandro <aleksandro@gmx.com> - 2016-01-20 12:54 -0300

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