Exercise – Scope

by heenan

JavaScript

/**
 * Exercise:
 *
 * Function Scope
 *
 * Work in the console, or use "console.log()" to output to the console 
 * from the script
 *
 * You could also use console.assert(boolean) to test your functions
 *
 * Part 1: Write two functions that share the same, global variable
 * 	- Verify this by logging the value of the variable to the console 
 *    from within each function
 */
 
 // write solution to part 1 here
 var x = 5;
 
 function a() {
 	console.log(x);
 }
 function b() {
 	console.log(x + 5);
 }
 a();
 b();
 
 
 /*
 * Part 2: Write two functions that share a non-global variable
 *  - Verify this by logging the value of the variable to the console 
 *    from within each function
 *
 *    Hint: You can write functions inside of other functions...
 */
 
 // write solution to part 2 here
 var x = 0;
 
 function c() {
  var y = 3;
  console.log(x);
  
  function d() {
  	console.log(x + y);
  }
  function e() {
  	var x = 4;
  	console.log(x + y);
  }
  
  d();
  e();
 }
 c();
 
 
  /*
 * Bonus: Write a function (outer) that returns another function (inner)
 *
 * The outer function expects one Number parameter, x
 * The inner function should add 1 to x and log it to the console
 * 
 * Hint: You will need to run the outer function once
 * in order to get the inner function
 */
 
 // write solution to bonus here
 /*
 function outer(x) {
  inner();
 	function inner() {
  	console.log(x+1);
  }
 }
 outer(5);
 */
 
  function outer(x) {
 
   return function inner() {
      x = x+1;
      console.log(x);
   }
 }

console.group('Bonus');
var inner = outer(5);
inner();
inner();
inner();