GirlBossRush · March 31, 2015 07:08
diff --git a/prototype-modification.js b/prototype-modification.js
 var foo = ['a', 'b']

 foo.first() // Uncaught TypeError: undefined is not a function
 Array.prototype.first = function () { return this[0] }
 foo.first() // "a"
	var foo = ['a', 'b']

	foo.first() // Uncaught TypeError: undefined is not a function
	Array.prototype.first = function () { return this[0] }
	foo.first() // "a"