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Re: Scope of "this" variable

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Joao Rodrigues wrote:

> On 29/12/2015 19:38, Joao Rodrigues wrote:
>> On 29/12/2015 17:34, Teemu Likonen wrote:
>>> I know a work-around:
>>>
>>>      var Item = function() {
>>>          this.variable = "variable";
>>>          this.fn1 = function() { return this.variable; };
>>>          var this_object = this;
>>>          this.foo = {
>>>              fn2: function() { return this_object.variable; }
>>                                         ^^^^^^^^^^^^
>>
>> Oops, this is something else, not a workaround, as this_object
>> references Item.variable, not foo.variable as in the previous case.
> 
> Oops again :-) I meant "as this_object.variable" references
> Item.variable..."

Nonsense.  “this” in the context of “Item”, therefore “this_object” too, 
refers to

  - the global object if the object referred to by “Item” (“Item”)
    is called as a global function in non-strict mode (in strict mode,
    “this” would be “undefined”)

  - the constructed Item instance if “Item” is called as a constructor

  - the object that “Item” was called as a function of through method
    transfer (“target.method = source.method; target.method(…)”), or use
    of Function.prototype.call(), Function.prototype.apply() (both since
    ES 3), or Function.prototype.bind() (since ES 5.x).

-- 
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Thread

Scope of "this" variable Teemu Likonen <tlikonen@iki.fi> - 2015-12-29 21:34 +0200
  Re: Scope of "this" variable Ben Bacarisse <ben.usenet@bsb.me.uk> - 2015-12-29 20:47 +0000
    Re: Scope of "this" variable Teemu Likonen <tlikonen@iki.fi> - 2015-12-30 10:57 +0200
  Re: Scope of "this" variable Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2015-12-29 22:09 +0100
  Re: Scope of "this" variable Joao Rodrigues <groups_jr-1@yahoo.com.br> - 2015-12-29 19:38 -0200
    Re: Scope of "this" variable Joao Rodrigues <groups_jr-1@yahoo.com.br> - 2015-12-29 19:46 -0200
      Re: Scope of "this" variable Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2015-12-30 00:42 +0100
    Re: Scope of "this" variable Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2015-12-30 00:35 +0100
    Re: Scope of "this" variable Joao Rodrigues <groups_jr-1@yahoo.com.br> - 2015-12-30 02:18 -0200

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