JavaScript Safer 'this' in depth look

I am currently reading Kyle Simpson's series You Don't Know JavaScript (YDKJS) and I am learning a lot about JavaScript. I have been writing his code examples and other JavaScript blog code examples in my plunker. I decided to code out his warning for using a safer this.

	var objNull = null;
	var emptyObjLiteral = {};
	// our DMZ(safe) empty object
	var emptyObj = Object.create( null );

view raw diffTypesOfEmptyObjects.txt hosted with ❤ by GitHub

	var objNull = null;
	var emptyObjLiteral = {};
	// our DMZ(safe) empty object
	var emptyObj = Object.create( null );

view raw diffTypesOfEmptyObjects.txt hosted with ❤ by GitHub

Kyle mentioned that null could mutate or reference the global object in a function that makes a 'this' reference in either your own code or in a third party library.

	function foo() {
	console.log(this === window);//true
	}
	foo.call( null );

view raw pitfallUsingNull hosted with ❤ by GitHub

The empty object literal {} still has __proto__ since it inherited from 'Object'.

If you use a third party library or you have code that checks for properties on 'this' then you could have a difficult bug.

	function foo() {<br/>
	if (this['toString']) {<br/>
	console.log('oops'); //this has .toString
	}
	}
	foo.call( {} );

view raw sideEffectOfEmptyObjectLiteral hosted with ❤ by GitHub

Object.create(null) truly is more empty than {}. It has no properties which makes it the safer 'this' option.