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Re: Can somebody explain this code

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On 04/05/16 00:51, Thomas 'PointedEars' Lahn wrote:
> Aleksandro wrote:
> 
>> On 27/03/16 20:07, Thomas 'PointedEars' Lahn wrote:
>>> Aleksandro wrote:
>>>> On 27/03/16 17:44, Thomas 'PointedEars' Lahn wrote:
>>>>> Aleksandro wrote:
>>>>>> On 24/03/16 16:30, Thomas 'PointedEars' Lahn wrote:
>>>>>>>   var myFunc;
>>>>>>>   myFunc = function () { alert("This is my anonymous function"); };
>>>>>>>
>>>>>>> (In that case, “myFunc” is assigned the “undefined” value first.)
>>>>>> Would the VM actually assign undefined first? I doubt it.
>>>>> On what grounds?
>>>> Well, there's a thing called optimization... you know...
>>> Although successive lines, they are not necessarily processed so.
>>
>> But they might.
> 
> I am not convinced.
> 
> There are at least four points that you are overlooking here:
> 
> 1. It was an *example* demonstrating functional equivalence of lines of
>    source code.
> 
> 2. myFunc = function () { alert("This is my anonymous function"); };
>    var myFunc;
>    
>    is equivalent to the previous code, too.
> 
> 3. There can be source code between declaration and assignment, and in the 
>    assignment, referring to the variable.  The value of the variable has to
>    be the “undefined” value then.

That is a totally different scenario that will most certainly be
optimized as well.

> 4. There is not only one virtual machine.  It need not even *be* a *virtual*
>    machine; for example, Google V8 JIT-compiles source code directly into 
>    machine code.
> 
>    <https://developers.google.com/v8/design>

And that JIT-compiler can make the same inferences.

> Taking unnecessary risks based on wild guesses and wishful thinking is the 
> mark of a wannabe.

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Thread

Can somebody explain this code "Tony Johansson" <johansson.andersson@telia.com> - 2016-03-23 22:51 +0100
  Re: Can somebody explain this code Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2016-03-24 20:30 +0100
    Re: Can somebody explain this code Aleksandro <aleksandro@gmx.com> - 2016-03-24 20:19 -0300
      Re: Can somebody explain this code Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2016-03-27 22:44 +0200
        Re: Can somebody explain this code Aleksandro <aleksandro@gmx.com> - 2016-03-27 18:22 -0300
          Re: Can somebody explain this code Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2016-03-28 01:07 +0200
            Re: Can somebody explain this code Aleksandro <aleksandro@gmx.com> - 2016-03-27 20:26 -0300
              Re: Can somebody explain this code Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2016-05-04 05:51 +0200
                Re: Can somebody explain this code "Evertjan." <exxjxw.hannivoort@inter.nl.net> - 2016-05-04 08:55 +0200
                Re: Can somebody explain this code Aleksandro <aleksandro@gmx.com> - 2016-05-07 13:02 -0300

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