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Re: Script in <a > tag in IE

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Richard Cornford wrote:

> I have tried this (a few years back), and as I remember Firefox and
> Chrome where actually first instantiating the compiling/function objects
> at the moment of reading the, for example, - onclick - property of the
> offending element. That is, it appear to be the getters for the
> intrinsic event properties that were actually creating the function
> object. Which makes more sense than waiting for an actual event needing
> to be handled because it is, in principle, possible for javascript code
> to access the property prior to any events being triggered, but the
> event handling process is still going to have to get the function object
> before it can call it.

Although it looks as though a DOM implementation's event handler would 
[[Call]] the Function instance that is the event listener, it is actually 
calling code that results from compiling the Function code into either 
bytecode for a Virtual Machine or native machine code.  So it is possible 
that with event-handler attributes no Function instance at all is being 
created unless user code accesses the corresponding event-handler property.  
(AFAIK there is no built-in way to retrieve an event listener added with 
EventTarget::addEventListener().)

In addition to those possible factory-getters, I have learned recently that 
with Chromium/Chrome the issue is even more complex.  By contrast to e. g. 
Mozilla SpiderMonkey, which compiles to and executes bytecode, Google V8 
compiles to and executes native machine code (which I knew before); however, 
I did not know that code generation does not happen before the function is 
called and usually does not happen again (because different code paths are 
handled with hidden classes).  Finally, optimized machine code is being 
generated (once) for objects that are accessed often, so that subsequent 
accesses to them are faster.

See also <http://code.google.com/p/v8/>; I can highly recommend especially 
the second video.

-- 
PointedEars

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

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Script in <a  > tag in IE Tim Slattery <Slattery_T@bls.gov> - 2013-02-07 14:32 -0500
  Re: Script in <a  > tag in IE "Evertjan." <exxjxw.hannivoort@inter.nl.net> - 2013-02-07 20:47 +0100
    Re: Script in <a  > tag in IE Tim Slattery <Slattery_T@bls.gov> - 2013-02-07 15:08 -0500
      Re: Script in <a  > tag in IE Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2013-02-07 21:20 +0100
      Re: Script in <a  > tag in IE SAM <stephanemoriaux.NoAdmin@wanadoo.fr.invalid> - 2013-02-09 16:42 +0100
    Re: Script in <a  > tag in IE Tim Streater <timstreater@greenbee.net> - 2013-02-07 21:30 +0000
      Re: Script in <a  > tag in IE Denis McMahon <denismfmcmahon@gmail.com> - 2013-02-08 07:08 +0000
        Re: Script in <a  > tag in IE Christoph Becker <cmbecker69@gmx.de> - 2013-02-08 16:30 +0100
          Re: Script in <a  > tag in IE Tim Streater <timstreater@greenbee.net> - 2013-02-08 15:41 +0000
  Re: Script in <a  > tag in IE Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2013-02-07 21:02 +0100
    Re: Script in <a  > tag in IE Eric Bednarz <bednarz@fahr-zur-hoelle.org> - 2013-02-09 00:19 +0100
      Re: Script in <a  > tag in IE Eric Bednarz <bednarz@fahr-zur-hoelle.org> - 2013-02-09 00:25 +0100
      Re: Script in <a  > tag in IE Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2013-02-09 14:35 +0100
        Re: Script in <a  > tag in IE Eric Bednarz <bednarz@fahr-zur-hoelle.org> - 2013-02-09 22:27 +0100
  Re: Script in <a  > tag in IE Cezary Tomczyk <cezary.tomczyk@gmail.com> - 2013-02-09 20:33 +0100
    Re: Script in <a  > tag in IE Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2013-02-10 00:08 +0100
      Re: Script in <a  > tag in IE Cezary Tomczyk <cezary.tomczyk@gmail.com> - 2013-02-10 00:52 +0100
        Re: Script in <a  > tag in IE Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2013-02-10 01:07 +0100
          Re: Script in <a  > tag in IE Cezary Tomczyk <cezary.tomczyk@gmail.com> - 2013-02-10 01:20 +0100
            Re: Script in <a  > tag in IE Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2013-02-10 01:27 +0100
              Re: Script in <a  > tag in IE Cezary Tomczyk <cezary.tomczyk@gmail.com> - 2013-02-10 01:43 +0100
                Re: Script in <a  > tag in IE Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2013-02-10 13:55 +0100
                Re: Script in <a  > tag in IE Cezary Tomczyk <cezary.tomczyk@gmail.com> - 2013-02-10 20:38 +0100
                Re: Script in <a  > tag in IE Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2013-02-10 21:28 +0100
                Re: Script in <a  > tag in IE Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2013-02-10 21:37 +0100
                Re: Script in <a  > tag in IE Cezary Tomczyk <cezary.tomczyk@gmail.com> - 2013-02-10 22:56 +0100
                Re: Script in <a  > tag in IE Eric Bednarz <bednarz@fahr-zur-hoelle.org> - 2013-02-11 00:09 +0100
                Re: Script in <a  > tag in IE Eric Bednarz <bednarz@fahr-zur-hoelle.org> - 2013-02-11 00:30 +0100
                Re: Script in <a  > tag in IE Cezary Tomczyk <cezary.tomczyk@gmail.com> - 2013-02-11 00:43 +0100
                Re: Script in <a  > tag in IE Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2013-02-11 01:02 +0100
                Re: Script in <a  > tag in IE Eric Bednarz <bednarz@fahr-zur-hoelle.org> - 2013-02-11 01:16 +0100
                Re: Script in <a  > tag in IE Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2013-02-11 01:49 +0100
                Re: Script in <a  > tag in IE Eric Bednarz <bednarz@fahr-zur-hoelle.org> - 2013-02-11 17:59 +0100
                Re: Script in <a  > tag in IE Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2013-02-11 18:19 +0100
                Re: Script in <a > tag in IE Scott Sauyet <scott.sauyet@gmail.com> - 2013-02-11 13:03 -0800
                Re: Script in <a > tag in IE Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2013-02-11 22:09 +0100
                Re: Script in <a > tag in IE Scott Sauyet <scott.sauyet@gmail.com> - 2013-02-11 13:59 -0800
                Re: Script in <a > tag in IE "Richard Cornford" <Richard@litotes.demon.co.uk> - 2013-02-18 00:15 +0000
                Re: Script in <a > tag in IE Scott Sauyet <scott.sauyet@gmail.com> - 2013-02-21 12:33 -0800
                Re: Script in <a > tag in IE "Richard Cornford" <Richard@litotes.demon.co.uk> - 2013-02-22 00:59 +0000
                Re: Script in <a > tag in IE Scott Sauyet <scott.sauyet@gmail.com> - 2013-02-23 07:54 -0800
                Re: Script in <a > tag in IE Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2013-02-22 02:00 +0100
                Re: Script in <a > tag in IE Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2013-02-22 01:12 +0100
                Re: Script in <a  > tag in IE Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2013-02-11 01:38 +0100
                Re: Script in <a  > tag in IE Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2013-02-11 00:48 +0100
                Re: Script in <a  > tag in IE Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2013-02-11 01:09 +0100
                Re: Script in <a  > tag in IE Cezary Tomczyk <cezary.tomczyk@gmail.com> - 2013-02-20 00:07 +0100
        Re: Script in <a > tag in IE dhtml <dhtmlkitchen@gmail.com> - 2013-02-11 07:30 -0800

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