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Re: Can somebody explain this to me

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From "Christoph M. Becker" <cmbecker69@arcor.de>
Newsgroups comp.lang.javascript
Subject Re: Can somebody explain this to me
Date Thu, 08 Jan 2015 13:16:03 +0100
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John Harris wrote:

> On Wed, 07 Jan 2015 17:01:05 +0100, "Christoph M. Becker"
> <cmbecker69@arcor.de> wrote:
> 
>> John Harris wrote:
>>
>>> It is obvious that you, Thomas, are not familiar with C++ V-tables.
>>> They do exactly the same job as an ECMAScript prototype chain but are
>>> far more efficient and cannot be altered by the user code, or even
>>> accessed. 
>>>
>>> V-tables are the obvious data structures to do the job but the
>>> Standard allows compilers to use any means they wish. A compiler could
>>> even use ECMAScript prototype chains, but wouldn't as it would be too
>>> slow and unnecessarily complicated.
>>
>> I consider it rather unlikely that an ECMAScript implementation uses
>> vtables for property lookup; more likely they might use hash tables
>> caches to avoid repeated traversal of the prototype chain.
>>
>> However, claiming or even assuming is somewhat inappropriate for a
>> technical newsgroup -- a proof would be preferable.
> 
> I'm afraid you've misread what I wrote. I said that a C++ compiler is
> permitted to use prototype chains if it wishes to (but it never will
> wish to).

Indeed, I've misread your post.  Thanks for the clarification.

> I did not say anything about ECMAScript implementations. Indeed,
> V-tables are fixed arrays that rely on variables having fixed names
> and on no change by the program so are very unsuitable.

ACK

-- 
Christoph M. Becker

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Thread

Can somebody explain this to me "Tony Johansson" <johansson.andersson@telia.com> - 2015-01-06 00:48 +0100
  Re: Can somebody explain this to me Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2015-01-06 01:40 +0100
    Re: Can somebody explain this to me John Harris <niam@jghnorth.org.uk.invalid> - 2015-01-06 16:01 +0000
      Re: Can somebody explain this to me Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2015-01-06 17:26 +0100
        Re: Can somebody explain this to me Joao Rodrigues <groups_jr-1@yahoo.com> - 2015-01-07 00:45 -0200
          Re: Can somebody explain this to me Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2015-01-07 04:35 +0100
            Re: Can somebody explain this to me Joao Rodrigues <groups_jr-1@yahoo.com.br> - 2015-01-07 16:15 -0200
              Re: Can somebody explain this to me Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2015-01-07 21:20 +0100
                Re: Can somebody explain this to me "Evertjan." <exxjxw.hannivoort@inter.nl.net> - 2015-01-08 00:00 +0100
                Re: Can somebody explain this to me Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2015-01-08 00:09 +0100
                Re: Can somebody explain this to me "Evertjan." <exxjxw.hannivoort@inter.nl.net> - 2015-01-08 10:53 +0100
                Re: Can somebody explain this to me Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2015-01-08 16:17 +0100
                Re: Can somebody explain this to me "Evertjan." <exxjxw.hannivoort@inter.nl.net> - 2015-01-08 17:04 +0100
                Re: Can somebody explain this to me Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2015-01-08 19:02 +0100
        Re: Can somebody explain this to me John Harris <niam@jghnorth.org.uk.invalid> - 2015-01-07 15:37 +0000
          Re: Can somebody explain this to me "Christoph M. Becker" <cmbecker69@arcor.de> - 2015-01-07 17:01 +0100
            Re: Can somebody explain this to me John Harris <niam@jghnorth.org.uk.invalid> - 2015-01-08 10:43 +0000
              Re: Can somebody explain this to me "Christoph M. Becker" <cmbecker69@arcor.de> - 2015-01-08 13:16 +0100
          Re: Can somebody explain this to me Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2015-01-08 16:43 +0100
            Re: Can somebody explain this to me John Harris <niam@jghnorth.org.uk.invalid> - 2015-01-09 20:16 +0000
              Re: Can somebody explain this to me Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2015-01-09 22:11 +0100
                Re: Can somebody explain this to me John Harris <niam@jghnorth.org.uk.invalid> - 2015-01-10 16:58 +0000
                Re: Can somebody explain this to me Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2015-01-11 12:41 +0100
                Re: Can somebody explain this to me John Harris <niam@jghnorth.org.uk.invalid> - 2015-01-12 15:46 +0000
                Re: Can somebody explain this to me Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2015-01-12 18:01 +0100
                Re: Can somebody explain this to me John Harris <niam@jghnorth.org.uk.invalid> - 2015-01-13 10:38 +0000
                Re: Can somebody explain this to me John Harris <niam@jghnorth.org.uk.invalid> - 2015-01-14 16:06 +0000
              Re: Can somebody explain this to me Scott Sauyet <scott.sauyet@gmail.com> - 2015-01-21 13:00 -0800
                Re: Can somebody explain this to me Joao Rodrigues <groups_jr-1@yahoo.com> - 2015-01-21 20:53 -0200
                Re: Can somebody explain this to me John Harris <niam@jghnorth.org.uk.invalid> - 2015-01-22 11:43 +0000
                Re: Can somebody explain this to me Joao Rodrigues <groups_jr-1@yahoo.com.br> - 2015-01-22 10:20 -0200
                Re: Can somebody explain this to me John Harris <niam@jghnorth.org.uk.invalid> - 2015-01-23 19:42 +0000
                Re: Can somebody explain this to me Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2015-01-28 18:14 +0100
                Re: Can somebody explain this to me John Harris <niam@jghnorth.org.uk.invalid> - 2015-01-22 11:39 +0000
                Re: Can somebody explain this to me "Christoph M. Becker" <cmbecker69@arcor.de> - 2015-01-22 13:27 +0100
                Re: Can somebody explain this to me John Harris <niam@jghnorth.org.uk.invalid> - 2015-01-23 14:36 +0000
                Re: Can somebody explain this to me Scott Sauyet <scott.sauyet@gmail.com> - 2015-01-23 08:51 -0800
                Re: Can somebody explain this to me "Christoph M. Becker" <cmbecker69@arcor.de> - 2015-01-23 23:17 +0100
                Re: Can somebody explain this to me John Harris <niam@jghnorth.org.uk.invalid> - 2015-01-24 16:42 +0000
                Re: Can somebody explain this to me Scott Sauyet <scott.sauyet@gmail.com> - 2015-01-24 15:35 -0800
                Re: Can somebody explain this to me John Harris <niam@jghnorth.org.uk.invalid> - 2015-01-25 11:08 +0000
                Re: Can somebody explain this to me "Michael Haufe (TNO)" <tno@thenewobjective.com> - 2015-01-26 08:33 -0800
                Re: Can somebody explain this to me "Christoph M. Becker" <cmbecker69@arcor.de> - 2015-01-27 14:10 +0100
                Re: Can somebody explain this to me John Harris <niam@jghnorth.org.uk.invalid> - 2015-01-28 15:50 +0000
                Re: Can somebody explain this to me "Christoph M. Becker" <cmbecker69@arcor.de> - 2015-01-28 18:26 +0100
                Re: Can somebody explain this to me John Harris <niam@jghnorth.org.uk.invalid> - 2015-01-29 10:29 +0000
                Re: Can somebody explain this to me "Christoph M. Becker" <cmbecker69@arcor.de> - 2015-01-31 00:37 +0100
                Re: Can somebody explain this to me "Michael Haufe (TNO)" <tno@thenewobjective.com> - 2015-01-28 13:30 -0800
                Re: Can somebody explain this to me "Evertjan." <exxjxw.hannivoort@inter.nl.net> - 2015-01-28 22:40 +0100
                Re: Can somebody explain this to me John Harris <niam@jghnorth.org.uk.invalid> - 2015-01-29 10:32 +0000
                Re: Can somebody explain this to me John Harris <niam@jghnorth.org.uk.invalid> - 2015-01-29 10:23 +0000
                Re: Can somebody explain this to me John Harris <niam@jghnorth.org.uk.invalid> - 2015-01-29 11:04 +0000
                Re: Can somebody explain this to me "Michael Haufe (TNO)" <tno@thenewobjective.com> - 2015-01-26 08:21 -0800
                Re: Can somebody explain this to me Scott Sauyet <scott.sauyet@gmail.com> - 2015-01-26 11:10 -0800
                Re: Can somebody explain this to me Scott Sauyet <scott.sauyet@gmail.com> - 2015-01-22 06:36 -0800
      Re: Can somebody explain this to me Tim Streater <timstreater@greenbee.net> - 2015-01-06 17:34 +0000
        Re: Can somebody explain this to me "Christoph M. Becker" <cmbecker69@arcor.de> - 2015-01-06 19:03 +0100
          Re: Can somebody explain this to me John Harris <niam@jghnorth.org.uk.invalid> - 2015-01-07 15:07 +0000
            Re: Can somebody explain this to me "Christoph M. Becker" <cmbecker69@arcor.de> - 2015-01-07 16:41 +0100
              Re: Can somebody explain this to me Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2015-01-07 17:22 +0100
                Re: Can somebody explain this to me John Harris <niam@jghnorth.org.uk.invalid> - 2015-01-08 10:36 +0000
                Re: Can somebody explain this to me "Christoph M. Becker" <cmbecker69@arcor.de> - 2015-01-08 13:36 +0100
                Re: Can somebody explain this to me Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2015-01-08 17:54 +0100
                Re: Can somebody explain this to me "Christoph M. Becker" <cmbecker69@arcor.de> - 2015-01-08 19:48 +0100
                Re: Can somebody explain this to me Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2015-01-08 22:09 +0100
                Re: Can somebody explain this to me Joao Rodrigues <groups_jr-1@yahoo.com.br> - 2015-01-08 18:22 -0200
                Re: Can somebody explain this to me "Christoph M. Becker" <cmbecker69@arcor.de> - 2015-01-08 22:13 +0100
                Re: Can somebody explain this to me Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2015-01-08 22:25 +0100
              Re: Can somebody explain this to me John Harris <niam@jghnorth.org.uk.invalid> - 2015-01-08 10:25 +0000
                Re: Can somebody explain this to me "Evertjan." <exxjxw.hannivoort@inter.nl.net> - 2015-01-08 11:33 +0100

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