switch off lexical scoping in javascript

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Is it possible to change the lexical scoping of javascript so that functions use the variable scope that is in effect when they are evoked not when they were defined? In a nutshell can I change the scope chain associated with a function?

An example for this: I would like to be able to execute something like this without getting the error message, that y is not defined:

function f(){y+2};
function g(){
 var y=2;
 f();
 return y;
}
g();
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ppovoski On BEST ANSWER

Your question may be due to the misunderstanding of your issue. y is not defined in a functional scope of f(), and you never assign a value to it. The y in g() is scoped to that function.

In your example:

function f(){ y+2 };
function g(){
  var y=2;
  f();
  return y;
}
g();

If g() used the global y, then y in f() will be defined at run-time. Drop the var keyword in g() to create a global y at compilation-time.

function f(){ y+2 };
function g(){
  y=2;
  f();
  return y;
}
g();

NOTE: Creating globally scoped variable like this is possible, but NOT recommended. Since your example is contrived and only being used to understand scope, it won't hurt anything.