prof3ssorSt3v3/index.html

## index.html
<!DOCTYPE html>
<html lang="en">
  <head>
    <meta charset="UTF-8" />
    <meta name="viewport" content="width=device-width, initial-scale=1.0" />
    <title>Variable Existence</title>
    <script src="index.js" type="module"></script>
  </head>
  <body>
    <header>
      <h1>Checking for Variable Existence</h1>
    </header>
  </body>
</html>

## index.js
import { NAME, frodo } from './mod.js';
//gimli doesn't exist in mod.js

const log = console.log;

let num1 = 42;
let str1 = 'Steve';
let obj1 = { a: 123 };
let arr1 = [1, 2, 3];
const f1 = function () {
  console.log('f1 function');
};

try {
  f2();
} catch (err) {
  log('error');
  if (err.name === 'ReferenceError') {
    log('f2 does not exist');
    log(err.message);
  }
}

// log(typeof NAME);
// log(typeof frodo);
// log(typeof gimli);

// var num2 = 99;
// var f2 = function () {
//   console.log('f2 function');
// };
// function f3() {
//   console.log('f3 function');
// }
// log(window['num2']);
// log(window['f2']);
// log('f3' in window);

// log(typeof num1);
// log(typeof str1);
// log(typeof obj1);
// log(typeof arr1);
// log(typeof f1);
// log(typeof num2 === 'undefined');

## mod.js
export const NAME = 'Frodo';

export function frodo() {
  console.log('frodo');
}
	<!DOCTYPE html>
	<html lang="en">
	<head>
	<meta charset="UTF-8" />
	<meta name="viewport" content="width=device-width, initial-scale=1.0" />
	<title>Variable Existence</title>
	<script src="index.js" type="module"></script>
	</head>
	<body>
	<header>
	<h1>Checking for Variable Existence</h1>
	</header>
	</body>
	</html>
	import { NAME, frodo } from './mod.js';
	//gimli doesn't exist in mod.js

	const log = console.log;

	let num1 = 42;
	let str1 = 'Steve';
	let obj1 = { a: 123 };
	let arr1 = [1, 2, 3];
	const f1 = function () {
	console.log('f1 function');
	};

	try {
	f2();
	} catch (err) {
	log('error');
	if (err.name === 'ReferenceError') {
	log('f2 does not exist');
	log(err.message);
	}
	}

	// log(typeof NAME);
	// log(typeof frodo);
	// log(typeof gimli);

	// var num2 = 99;
	// var f2 = function () {
	// console.log('f2 function');
	// };
	// function f3() {
	// console.log('f3 function');
	// }
	// log(window['num2']);
	// log(window['f2']);
	// log('f3' in window);

	// log(typeof num1);
	// log(typeof str1);
	// log(typeof obj1);
	// log(typeof arr1);
	// log(typeof f1);
	// log(typeof num2 === 'undefined');
	export const NAME = 'Frodo';

	export function frodo() {
	console.log('frodo');
	}