freeCodeCamp/curriculum/challenges/english/02-javascript-algorithms-and-data-structures/basic-javascript/global-scope-and-functions.md

id, title, challengeType, videoUrl, forumTopicId, dashedName

id	title	challengeType	videoUrl	forumTopicId	dashedName
56533eb9ac21ba0edf2244be	Global Scope and Functions	1	https://scrimba.com/c/cQM7mCN	18193	global-scope-and-functions

--description--

In JavaScript, scope refers to the visibility of variables. Variables which are defined outside of a function block have Global scope. This means, they can be seen everywhere in your JavaScript code.

Variables which are declared without the let or const keywords are automatically created in the global scope. This can create unintended consequences elsewhere in your code or when running a function again. You should always declare your variables with let or const.

--instructions--

Using let or const, declare a global variable named myGlobal outside of any function. Initialize it with a value of 10.

Inside function fun1, assign 5 to oopsGlobal without using the var, let or const keywords.

--hints--

myGlobal should be defined

assert(typeof myGlobal != 'undefined');

myGlobal should have a value of 10

assert(myGlobal === 10);

myGlobal should be declared using the let or const keywords

assert(/(let|const)\s+myGlobal/.test(code));

oopsGlobal should be a global variable and have a value of 5

assert(typeof oopsGlobal != 'undefined' && oopsGlobal === 5);

--seed--

--before-user-code--

var logOutput = "";
var originalConsole = console
function capture() {
    var nativeLog = console.log;
    console.log = function (message) {
        logOutput = message;
        if(nativeLog.apply) {
          nativeLog.apply(originalConsole, arguments);
        } else {
          var nativeMsg = Array.prototype.slice.apply(arguments).join(' ');
          nativeLog(nativeMsg);
        }
    };
}

function uncapture() {
  console.log = originalConsole.log;
}
var oopsGlobal;
capture();

--after-user-code--

fun1();
fun2();
uncapture();
(function() { return logOutput || "console.log never called"; })();

--seed-contents--

// Declare the myGlobal variable below this line


function fun1() {
  // Assign 5 to oopsGlobal here

}

// Only change code above this line

function fun2() {
  let output = "";
  if (typeof myGlobal != "undefined") {
    output += "myGlobal: " + myGlobal;
  }
  if (typeof oopsGlobal != "undefined") {
    output += " oopsGlobal: " + oopsGlobal;
  }
  console.log(output);
}

--solutions--

const myGlobal = 10;

function fun1() {
  oopsGlobal = 5;
}

function fun2() {
  let output = "";
  if(typeof myGlobal != "undefined") {
    output += "myGlobal: " + myGlobal;
  }
  if(typeof oopsGlobal != "undefined") {
    output += " oopsGlobal: " + oopsGlobal;
  }
  console.log(output);
}