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Re: closure bindings

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Michael Haufe (TNO) wrote:

> Thomas 'PointedEars' Lahn wrote:
>> Michael Haufe (TNO) wrote:
>> > Thomas 'PointedEars' Lahn wrote:
>> >> BTW, how do you pass a *scope* to a method?
>>
>> > - pass "this" from the global scope to get a reference to it
>>
>> `this' has nothing to do with scope.
> 
> PowerShell has scope as an object to manipulate:
>     $global:foo = "bar";
>     $local:foo="bar";
>     $7:foo="bar";
> 
> In the JS family

Probably you mean ECMAScript implementations.

> this is not the case obviously, so one has to rely on
> unreliable hacks to emulate the effect. Each of the examples I'm
> referring to are an attempt at that, primarily in legacy
> implementations of the language.

This has nothing to do with "legacy implementations".
 
> So for the above, the emulated effect can be seen for this specific
> case:
> 
> var foo = "bar"
> 
> function test(s){
>     WScript.Echo(s.foo)
> }
> 
> test(this) //bar
>
> function change(s){
>     s.foo = "quux"
> }
> 
> change(this)
> 
> test(this) //quux

And AISB, and we discussed at length before, `this' has nothing to do with 
scope.  You can see that confirmed, not refuted, here.  It is only that the 
ECMAScript Global Object serves as the Variable Object for the global 
execution context (to avoid the even more complicated ES5 terminology) that 
it *appears* *as* if* the opposite was the case.

Wrap this in `(function() { … })()' and it will cease working (if it worked 
before), i. e. both test() calls will show `undefined', and in change() the 
global object will be added a `foo' property, if that.

>> > - use the deprecated someObject.eval in old FireFox (pre 3.0).
>>
>> While it is an item for the ECMAScript Support Matrix indeed, that has
>> nothing to do with passing an existing scope to *that* method as well.
> 
> The second argument of the deprecated eval and Object.eval work by
> executing
> code in a particular context which offers a means to change existing
> variables.
> So while it may not be passing scope as an object, it did provide a
> means to do
> some manipulation of the scope variables to a degree. I don't have an
> old
> Fx installed to play with this anymore, but I'm certain
> 
> arguments.callee.caller.eval(...)
> 
> would be pretty effective at wreaking havoc on existing items.

Something is awfully wrong with your posting agent or the way you use it.
I will not attempt to make sense of this mess.

>> > Perhaps something involving manipulation and passing of the arguments
>> > object...
>> But that also has nothing to do with (passing) scope.
> 
> And again, it at least provides a means of partially getting the
> effect of having one.

Only by chance and ignorance.


PointedEars
-- 
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(This won't prevent people from viewing your source, but no one
will want to steal it.)
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Google Dart Released Today dhtml <dhtmlkitchen@gmail.com> - 2011-10-10 10:44 -0700
  Re: Google Dart Released Today "Michael Haufe (TNO)" <tno@thenewobjective.com> - 2011-10-10 14:24 -0700
    Re: Google Dart Released Today dhtml <dhtmlkitchen@gmail.com> - 2011-10-10 22:36 -0700
      Re: Google Dart Released Today David Mark <dmark.cinsoft@gmail.com> - 2011-10-10 23:41 -0700
      Re: Google Dart Released Today "Michael Haufe (TNO)" <tno@thenewobjective.com> - 2011-10-11 05:33 -0700
        Re: Google Dart Released Today dhtml <dhtmlkitchen@gmail.com> - 2011-10-11 14:06 -0700
          Re: Google Dart Released Today Swifty <steve.j.swift@gmail.com> - 2011-10-12 07:13 +0100
      closure bindings (was: Google Dart Released Today) Andreas Bergmaier <andber93@web.de> - 2011-10-11 23:56 +0200
        Re: closure bindings (was: Google Dart Released Today) David Mark <dmark.cinsoft@gmail.com> - 2011-10-11 16:20 -0700
        Re: closure bindings Bwig Zomberi <zomberiMAPSONNOSPAM@gmail.invalid> - 2011-10-12 15:02 +0530
          Re: closure bindings Antony Scriven <adscriven@gmail.com> - 2011-10-12 05:12 -0700
            Re: closure bindings dhtml <dhtmlkitchen@gmail.com> - 2011-10-12 18:27 -0700
        Re: closure bindings Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2011-10-12 13:24 +0200
          Re: closure bindings "Michael Haufe (TNO)" <tno@thenewobjective.com> - 2011-10-12 08:56 -0700
            Re: closure bindings Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2011-10-12 21:15 +0200
              Re: closure bindings "Michael Haufe (TNO)" <tno@thenewobjective.com> - 2011-10-12 15:21 -0700
                Re: closure bindings Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2011-10-13 20:56 +0200
                Re: closure bindings Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2011-10-13 21:36 +0200
                Re: closure bindings "Michael Haufe (TNO)" <tno@thenewobjective.com> - 2011-10-13 16:41 -0700
                Re: closure bindings dhtml <dhtmlkitchen@gmail.com> - 2011-10-13 22:39 -0700
                Re: closure bindings "Michael Haufe (TNO)" <tno@thenewobjective.com> - 2011-10-14 09:03 -0700
                Re: closure bindings Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2011-10-14 20:05 +0200
              Re: closure bindings dhtml <dhtmlkitchen@gmail.com> - 2011-10-12 18:38 -0700
                Re: closure bindings Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2011-10-14 23:34 +0200
                Re: closure bindings dhtml <dhtmlkitchen@gmail.com> - 2011-10-14 16:56 -0700
                Re: closure bindings Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2011-10-15 02:44 +0200
                Re: closure bindings dhtml <dhtmlkitchen@gmail.com> - 2011-10-14 21:18 -0700
            Re: closure bindings David Mark <dmark.cinsoft@gmail.com> - 2011-10-12 18:28 -0700
      Re: Google Dart Released Today Antony Scriven <adscriven@gmail.com> - 2011-10-11 15:13 -0700
        Re: Google Dart Released Today dhtml <dhtmlkitchen@gmail.com> - 2011-10-11 22:33 -0700
      Re: Google Dart Released Today Scott Sauyet <scott.sauyet@gmail.com> - 2011-10-12 07:27 -0700
        Re: Google Dart Released Today dhtml <dhtmlkitchen@gmail.com> - 2011-10-12 18:29 -0700
        Re: Google Dart Released Today Duncan Booth <duncan.booth@invalid.invalid> - 2011-10-13 08:21 +0000
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            Re: Google Dart Released Today Karl Tikjøb Krukow <karl.krukow@gmail.com> - 2011-10-14 13:02 +0200
              Re: Google Dart Released Today dhtml <dhtmlkitchen@gmail.com> - 2011-10-14 12:36 -0700
                Re: Google Dart Released Today Karl Tikjøb Krukow <karl.krukow@gmail.com> - 2011-10-15 19:30 +0200
  Re: Google Dart Released Today David Mark <dmark.cinsoft@gmail.com> - 2011-10-10 22:23 -0700
  Re: Google Dart Released Today Matt McDonald <matt@fortybelow.ca> - 2011-10-12 19:48 -0600
    Re: Google Dart Released Today dhtml <dhtmlkitchen@gmail.com> - 2011-10-12 21:04 -0700

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