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Re: Overwriting existing fucntion

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On 2015-10-19 19:49, Thomas 'PointedEars' Lahn wrote:
> Different to what Stefan suggested, you should not be using “window” to 
> refer to the global object, but if you need to make it explicit, “this” in 
> the global execution context.  For example
> 
>   /* global context */
>   var global = this;

This will not give you the global object, but rather the window object
again (actually, the window's WindowProxy object) in HTML5:

| A global object
|
| An object that provides the APIs that can be called by the code in
| scripts that use this settings object.
|
| Note: This is typically a Window object or a WorkerGlobalScope
| object. When a global object is an empty object, it can't do anything
| that interacts with the environment.
|
| If the global object is a Window object, then, in JavaScript, the
| ThisBinding of the global execution context for this script must
| be the Window object's WindowProxy object, rather than the global
| object. [ECMA262]
|
| Note: This is a willful violation of the JavaScript specification
| current at the time of writing (ECMAScript edition 5, as defined
| in section 10.4.1.1 Initial Global Execution Context, step 3). The
| JavaScript specification requires that the this keyword in the
| global scope return the global object, but this is not compatible
| with the security design prevalent in implementations as specified
| herein. [ECMA262]

http://www.w3.org/TR/html5/webappapis.html#global-object

Even before HTML5, I've never heard of a browser in which `window` in
the global context would be anything other than a host object giving
access to the global object's properties - barring non-document
contexts, shadowing, obsolete browsers, and bugs. Unless you're doing
something very unusual, the warning to not rely on `window` is unnecessary.


- stefan

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Thread

Overwriting existing fucntion Andrew Poulos <ap_prog@hotmail.com> - 2015-10-19 12:12 +1100
  Re: Overwriting existing fucntion Andrew Poulos <ap_prog@hotmail.com> - 2015-10-19 13:57 +1100
  Re: Overwriting existing fucntion Stefan Weiss <krewecherl@gmail.com> - 2015-10-19 05:04 +0200
    Re: Overwriting existing fucntion Stefan Weiss <krewecherl@gmail.com> - 2015-10-19 13:14 +0200
  Re: Overwriting existing fucntion Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2015-10-19 19:49 +0200
    Re: Overwriting existing fucntion Andrew Poulos <ap_prog@hotmail.com> - 2015-10-20 10:18 +1100
      Re: Overwriting existing fucntion Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2015-10-20 02:17 +0200
    Re: Overwriting existing fucntion Stefan Weiss <krewecherl@gmail.com> - 2015-10-21 19:47 +0200
      Re: Overwriting existing fucntion Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2015-10-21 21:40 +0200
        Re: Overwriting existing fucntion Stefan Weiss <krewecherl@gmail.com> - 2015-10-22 03:04 +0200
  Re: Overwriting existing fucntion Danny <dann90038@gmail.com> - 2015-10-19 13:29 -0700

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