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Re: Importing multiple .js files

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Eric Bednarz wrote:

> Thomas 'PointedEars' Lahn <PointedEars@web.de> writes:
>> Eric Bednarz wrote:
>>> 2) Loading a really large file is usually much less efficient than
>>> loading several smaller files dynamically in parallel in most (more or
>>> less) contemporary browsers. This might depend on the precise values of
>>> 'several' and 'contemporary', of course.
>>
>> How did you get that idea?  You are also not considering that the number
>> of parallel HTTP requests is limited,
> 
> ... to an average of 6 to 8 requests per hostname, these days.

How did you get that idea?

> We were talking about less than ten scripts.

Were we?

> Map that to 'usually'.

If we must go down that slippery road: unfortunately, the average script-
kiddie makes sure that “usually” means more than 9 by now.

>> not only by HTTP/1.1 definitions,
> 
> But also by gut feeling. You're right, I didn't consider.
> 
>> and that even if parallel download is possible, parallel parsing is
>> not.
> 
> As you would say, this is a fallacious argument. If you load /n/ scripts
> in parallel in a non-blocking way and parse them sequentially, that's
> usually faster because:
> 
> - one script can be parsed while another one downloads

No, in general it cannot.  As I have had to realize with regard to my code,

  /* part 1 */
  var f = function () {};

  /* part 2 */
  var f2 = (function () {
    /* function */
    var _f = f;

    return function () {
      return _f;
    };
  }());

has a different result than
  
  /* part 1 */
  var f2 = (function () {
    /* undefined */
    var _f = f;

    return function () {
      return _f;
    };
  }());

  /* part 2 */
  var f = function () {};

> - meanwhile, the DOM can be parsed, too

No, it (the _document_; the DOM is an *API* instead) cannot: Client-side 
scripts can modify the document while it is being parsed.  Therefore, it is 
BCP to put stylesheet references and stylesheets before client-side script 
references and client-side scripts (so that stylesheets can be applied while 
scripts are loaded and parsed), and to avoid document.write() in favor of 
.appendChild().  [The ES Matrix explicitly uses document.write() for 
backwards compatibility.]

There is one exception to this rule, and that is when the (formerly, 
proprietary) “defer” attribute is specified on the “script” element, *and* 
supported (but document.write() cannot be used there).

-- 
PointedEars

Twitter: @PointedEars2
Please do not Cc: me. / Bitte keine Kopien per E-Mail.

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Importing multiple .js files "Robert Crandal" <rcranz143101@gmail.com> - 2013-10-25 03:09 -0700
  Re: Importing multiple .js files Stefan Weiss <krewecherl@gmail.com> - 2013-10-25 13:06 +0200
    Re: Importing multiple .js files Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2013-10-25 22:18 +0200
      Re: Importing multiple .js files "Jukka K. Korpela" <jkorpela@cs.tut.fi> - 2013-10-26 00:05 +0300
        Re: Importing multiple .js files Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2013-10-25 23:54 +0200
          Re: Importing multiple .js files John Harris <niam@jghnorth.org.uk.invalid> - 2013-10-27 14:05 +0000
            Re: Importing multiple .js files Christoph Michael Becker <cmbecker69@arcor.de> - 2013-10-27 17:05 +0100
              Re: Importing multiple .js files John Harris <niam@jghnorth.org.uk.invalid> - 2013-10-28 15:40 +0000
                Re: Importing multiple .js files Ben Bacarisse <ben.usenet@bsb.me.uk> - 2013-10-28 15:49 +0000
                Re: Importing multiple .js files John Harris <niam@jghnorth.org.uk.invalid> - 2013-10-29 16:29 +0000
                Re: Importing multiple .js files Ben Bacarisse <ben.usenet@bsb.me.uk> - 2013-10-29 20:41 +0000
                Re: Importing multiple .js files John Harris <niam@jghnorth.org.uk.invalid> - 2013-10-31 09:31 +0000
                Re: Importing multiple .js files Ben Bacarisse <ben.usenet@bsb.me.uk> - 2013-10-31 13:30 +0000
                Re: Importing multiple .js files Christoph Michael Becker <cmbecker69@arcor.de> - 2013-10-29 22:13 +0100
                Re: Importing multiple .js files Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2013-10-30 00:50 +0100
                Re: Importing multiple .js files John Harris <niam@jghnorth.org.uk.invalid> - 2013-10-31 15:52 +0000
                Re: Importing multiple .js files Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2013-10-31 17:19 +0100
                Re: Importing multiple .js files John Harris <niam@jghnorth.org.uk.invalid> - 2013-11-01 15:27 +0000
                Re: Importing multiple .js files Christoph Michael Becker <cmbecker69@arcor.de> - 2013-10-31 18:34 +0100
                Re: Importing multiple .js files "Jukka K. Korpela" <jkorpela@cs.tut.fi> - 2013-10-31 20:36 +0200
                FAQ discussion (was: Importing multiple .js files) Christoph Michael Becker <cmbecker69@arcor.de> - 2013-10-31 20:33 +0100
                Re: FAQ discussion Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2013-11-06 12:20 +0100
                Re: FAQ discussion Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2013-11-06 14:33 +0100
                Re: Importing multiple .js files John Harris <niam@jghnorth.org.uk.invalid> - 2013-11-01 15:12 +0000
                "javascript" (was: Importing multiple .js files) Christoph Michael Becker <cmbecker69@arcor.de> - 2013-11-04 18:36 +0100
                Re: "javascript" (was: Importing multiple .js files) Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2013-11-05 02:41 +0100
    Re: Importing multiple .js files Eric Bednarz <bednarz@fahr-zur-hoelle.org> - 2013-10-27 00:30 +0200
      Re: Importing multiple .js files Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2013-10-27 00:58 +0200
        Re: Importing multiple .js files Eric Bednarz <bednarz@fahr-zur-hoelle.org> - 2013-10-27 01:27 +0200
          Re: Importing multiple .js files Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2013-10-27 02:37 +0200
            Re: Importing multiple .js files Eric Bednarz <bednarz@fahr-zur-hoelle.org> - 2013-10-27 09:49 +0100
              Re: Importing multiple .js files Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2013-10-27 15:38 +0100
                Re: Importing multiple .js files Eric Bednarz <bednarz@fahr-zur-hoelle.org> - 2013-10-27 16:11 +0100
                Re: Importing multiple .js files Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2013-10-27 20:16 +0100
      Re: Importing multiple .js files Stefan Weiss <krewecherl@gmail.com> - 2013-10-27 02:01 +0100
        Re: Importing multiple .js files danca <cyberdanny@tiscalinet.it> - 2013-10-27 11:30 +0100
  Re: Importing multiple .js files nappysoft <nappysoft@gmail.com> - 2013-11-21 05:53 -0800
    Re: Importing multiple .js files Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2013-11-21 16:15 +0100

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