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Re: onclick=function(){obj.meth()}

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Richard Cornford wrote:

> Puzzled wrote:> On Mon, 20 Feb 2012 23:17:42 +0100,
>> This is what I'm trying to do:
>>
>> onclick = "this.some_method_identifier( arg, arg )"
> 
> That is meaningless in javascript terms precisely because the value of
> the - this - keyword is not decided at this point.

Incorrect.  `this' in an event-handler *attribute* value is and always has 
been a reference to the DOM object representing the element having that 
attribute value.

However, issues arise if `some_method_identifier' is not a stand-in for a 
built-in method of that DOM object or an object in its prototype chain.  A 
DOM object is a host object, and per the ECMAScript Language Specification 
the algorithms of the Specification, including the `[[Put]]' and `[[Get]]' 
algorithms to set and retrieve property values, respectively, do not need to 
be implemented as specified.  IOW:

  With host objects, all bets are off.
    -- (attributed to) Lasse Reichstein Nielsen
 
>> and should be able to grasp that when I use it in a binding,
> 
> Presumably you are using "terp" as an abbreviation for interpreter.
> 
> In javascript the value of the - this - keyword is (always and only)
> decided at runtime, 

Which is precisely why the followed approach may work, given the right 
method call. 

> so the interpreter cannot know what the value will be at the time of
> tokenising/parsing/compiling the code.

It does not have to in this case.

>> I thought the proxy and the anon function were the required magic, be
>> evidently not so, so now I'm back where I started, neck deep in
>> confusion and ignorance.
> 
> Computer programming is about understand enough to take control, which
> is the antithesis of  'magic'.

ACK.


PointedEars
-- 
Anyone who slaps a 'this page is best viewed with Browser X' label on
a Web page appears to be yearning for the bad old days, before the Web,
when you had very little chance of reading a document written on another
computer, another word processor, or another network. -- Tim Berners-Lee

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onclick=function(){obj.meth()} Puzzled <scratching.head@example.com> - 2012-02-20 14:02 -0500
  Re: onclick=function(){obj.meth()} "Tom de Neef" <tdeneef@qolor.nl> - 2012-02-20 20:20 +0100
    Re: onclick=function(){obj.meth()} Jake Jarvis <pig_in_shoes@yahoo.com> - 2012-02-20 20:39 +0100
      Re: onclick=function(){obj.meth()} "Richard Cornford" <Richard@litotes.demon.co.uk> - 2012-02-21 00:34 +0000
        Re: onclick=function(){obj.meth()} Stefan Weiss <krewecherl@gmail.com> - 2012-02-21 02:13 +0100
          Re: onclick=function(){obj.meth()} Richard Cornford <Richard@litotes.demon.co.uk> - 2012-02-21 04:05 -0800
        Re: onclick=function(){obj.meth()} Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2012-02-21 12:47 +0100
          Re: onclick=function(){obj.meth()} John G Harris <john@nospam.demon.co.uk> - 2012-02-21 15:59 +0000
  Re: onclick=function(){obj.meth()} Stefan Weiss <krewecherl@gmail.com> - 2012-02-20 21:09 +0100
    Re: onclick=function(){obj.meth()} "Evertjan." <exjxw.hannivoort@interxnl.net> - 2012-02-20 20:29 +0000
      Re: onclick=function(){obj.meth()} Puzzled <scratching.head@example.com> - 2012-02-20 16:50 -0500
        Re: onclick=function(){obj.meth()} "Evertjan." <exjxw.hannivoort@interxnl.net> - 2012-02-21 11:33 +0000
    Re: onclick=function(){obj.meth()} Puzzled <scratching.head@example.com> - 2012-02-20 15:47 -0500
      Re: onclick=function(){obj.meth()} Jake Jarvis <pig_in_shoes@yahoo.com> - 2012-02-20 22:38 +0100
        Re: onclick=function(){obj.meth()} Puzzled <scratching.head@example.com> - 2012-02-20 17:12 -0500
      Re: onclick=function(){obj.meth()} Gene Wirchenko <genew@ocis.net> - 2012-02-20 14:04 -0800
        "The this value" (Was: onclick=function(){obj.meth()}) Stefan Weiss <krewecherl@gmail.com> - 2012-02-21 01:37 +0100
          Re: "The this value" (Was: onclick=function(){obj.meth()}) Gene Wirchenko <genew@ocis.net> - 2012-02-20 17:20 -0800
          Re: "The this value" (Was: onclick=function(){obj.meth()}) Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2012-02-21 13:44 +0100
            Re: "The this value" (Was: onclick=function(){obj.meth()}) Stefan Weiss <krewecherl@gmail.com> - 2012-02-21 22:31 +0100
              Re: "The this value" (Was: onclick=function(){obj.meth()}) Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2012-02-22 10:55 +0100
                Re: "The this value" (Was: onclick=function(){obj.meth()}) John G Harris <john@nospam.demon.co.uk> - 2012-02-22 15:58 +0000
        Re: onclick=function(){obj.meth()} "Richard Cornford" <Richard@litotes.demon.co.uk> - 2012-02-21 01:30 +0000
      Re: onclick=function(){obj.meth()} Scott Sauyet <scott.sauyet@gmail.com> - 2012-02-20 13:43 -0800
      Re: onclick=function(){obj.meth()} Stefan Weiss <krewecherl@gmail.com> - 2012-02-20 23:17 +0100
        Re: onclick=function(){obj.meth()} Puzzled <scratching.head@example.com> - 2012-02-20 17:48 -0500
          Re: onclick=function(){obj.meth()} Stefan Weiss <krewecherl@gmail.com> - 2012-02-21 00:57 +0100
          Re: onclick=function(){obj.meth()} "Richard Cornford" <Richard@litotes.demon.co.uk> - 2012-02-21 01:03 +0000
            Re: onclick=function(){obj.meth()} Gene Wirchenko <genew@ocis.net> - 2012-02-20 19:05 -0800
              Re: onclick=function(){obj.meth()} Richard Cornford <Richard@litotes.demon.co.uk> - 2012-02-21 04:14 -0800
                Re: onclick=function(){obj.meth()} Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2012-02-21 13:54 +0100
                Re: onclick=function(){obj.meth()} Gene Wirchenko <genew@ocis.net> - 2012-02-21 10:17 -0800
                Re: onclick=function(){obj.meth()} Scott Sauyet <scott.sauyet@gmail.com> - 2012-02-21 11:57 -0800
                Re: onclick=function(){obj.meth()} Gene Wirchenko <genew@ocis.net> - 2012-02-21 13:39 -0800
                Re: onclick=function(){obj.meth()} Scott Sauyet <scott.sauyet@gmail.com> - 2012-02-22 05:07 -0800
            Re: onclick=function(){obj.meth()} Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2012-02-21 12:58 +0100
        Re: onclick=function(){obj.meth()} "Richard Cornford" <Richard@litotes.demon.co.uk> - 2012-02-21 00:45 +0000
          Re: onclick=function(){obj.meth()} Stefan Weiss <krewecherl@gmail.com> - 2012-02-21 02:22 +0100
        Re: onclick=function(){obj.meth()} Puzzled <scratching.head@example.com> - 2012-02-21 08:12 -0500
          Re: onclick=function(){obj.meth()} Scott Sauyet <scott.sauyet@gmail.com> - 2012-02-21 11:14 -0800

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