change JavaScript scope

Is there any posibility to exchange the special global window scope by a custom one? I just thought with is meant to, but it only stacks another "lookup" scope. Eg.

test={};
with(test){
    a=1;
}

does not create the property test.a but window.a.

So the window object has a JS-specific specia开发者_如何转开发l quality I cannot recreate with own code?

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If the property exists on the object given to with then it will be modified, but it will never be created. This is a major "gotcha" with using with and the primary reason it should be avoided.

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With with only if the object passed in has that property, will it be modified. It will not be created.

http://www.yuiblog.com/blog/2006/04/11/with-statement-considered-harmful/