35.double-equal-to.js

/*
	# == - double equal to operator does type conversion then checks for its equality.

	# Truth table - https://dorey.github.io/JavaScript-Equality-Table/
	
	## Reference 
	1. http://stackoverflow.com/questions/359494/which-equals-operator-vs-should-be-used-in-javascript-comparisons?answertab=active#tab-top
	2. https://appendto.com/2016/02/vs-javascript-abstract-vs-strict-equality/
*/

// Examples using Number and String

console.log(0 == ""); // true

console.log("" == 0); // true

console.log(1 == true); // true & same goes for in reverse

console.log(10 == "10"); // true

console.log(-1 == "-1"); // true

// Examples using Array
console.log([1] == true); // true

console.log([] == true); // false

var arr1 = [1];
var arr2 = [2];

console.log(arr1 == arr2); // false

console.log([0] == true); // false

console.log([0] == false); // true

console.log([[]] == false); // true

console.log([1,2,3] == "1,2,3"); // true

// Examples using Object
var obj1 = {a: 1};
var obj2 = {a: 1};

console.log(obj1 == obj2); // false

console.log(undefined == null); // true

console.log("xyz" == new String("xyz")); // true

console.log(typeof "xyz"); // string

console.log(typeof new String("xyz")); // object