How Can We Get The Execution Context Of A Function?

Let say we declare a variable in the global context, like so: var someVariable = 'someValue'; We can always access its value like window['someVariable'] as it is in the global exe

Solution 1:

That's not possible without returning objects or instantiating the function and accessing the property.

Global variables are automatically a property of the window object, provided you use var and not let or const. Such as root level functions being automatically a method of the window object. But functions do not behave like primitive objects. You need to do something like

function Favorites(){
  return{
     food: "burrito",
     color: "gray"
  }
}

var fav = Favorites();
var favfood = fav.food; //fav['food']

OR

function Favorites(){
  this.food = "burrito";
  this.color = "gray";
}

var fav = new Favorites();
var favfood = fav.food; //fav['food']

And like so

var favfood = window.fav.food;
var favcolor = window['fav']['color']

Solution 2:

One of the approach could be exposing certain properties of the function itself.

function fn(){
  fn.num = 100;
}
//access fn.num
console.log(fn["num"])

You can control which properties you want to expose from the function itself. For example,

function doSomething(num, addStr){
  //expose num
  doSomething.num = num;
  var str = "Hello ";
  if(addStr){
    str += addStr;
  }
  //expose str
  doSomething.str = str;
}

//set num
doSomething(100);

//access num
console.log(doSomething.num)
console.log(doSomething["num"])

//set num and str
doSomething(200, "Jerry!")

//access str
console.log(doSomething["str"])