02-Variables.js

// @ts-check

var num = 1; // {1}
num = 3; // {2}

var price = 1.5; // {3}
var name = 'Packt'; // {4}
var trueValue = true; // {5}
var nullVar = null; // {6}
var und; // {7}

console.log('num: ' + num);
console.log('name: ' + name);
console.log('trueValue: ' + trueValue);
console.log('price: ' + price);
console.log('nullVar: ' + nullVar);
console.log('und: ' + und);

// ******* Variable Scope

var myVariable = 'global';
myOtherVariable = 'global';

function myFunction() {
  var myVariable = 'local';
  return myVariable;
}

function myOtherFunction() {
  myOtherVariable = 'local';
  return myOtherVariable;
}

console.log(myVariable); //{1}
console.log(myFunction()); //{2}

console.log(myOtherVariable); //{3}
console.log(myOtherFunction()); //{4}
console.log(myOtherVariable); //{5}