Read:

• JavaScript : Closures

• Everything you wanted to know about JavaScript scope

• JavaScript Scoping and Hoisting

• 5 JavaScript “Bad” Parts That Are Fixed In ES6

• More about closures

• A VERY popular StackOverflow article

Let's continue to learn a little more about scope and Closures.

2. What will be the output of the following code - and more importantly - WHY?

for (var i = 0; i < 3; i++) {
      setTimeout(function() { alert(i); }, 1000 + i);
}

3. Write a function that would allow you to do this:

let addSix = createBase(6);
addSix(10); // returns 16
addSix(21); // returns 27

4. You will need to create an HTML document out of the below snippet to run the below code. A hint - the code is syntactically correct but doesn't do what you would expect. Can you see why and fix it?

Don't cheat - but if you get stuck ... http://stackoverflow.com/questions/750486/javascript-closure-inside-loops-simple-practical-example

<button id="btn-0">Button 1!</button>
<button id="btn-1">Button 2!</button>
<button id="btn-2">Button 3!</button>

<script type="text/javascript">
    
    let prizes = ['A Unicorn!', 'A Hug!', 'Fresh Laundry!'];
    for (let btnNum = 0; btnNum < prizes.length; btnNum++) {
        // for each of our buttons, when the user clicks it...
        document.getElementById('btn-' + btnNum).onclick = function() {
            // tell her what she's won!
            alert(prizes[btnNum]);
        };
    }
</script>

5. Rewrite the code below to Async:

1.

let sum = calculateSum(2, 6);
console.log(sum);

2.

let results = $.getJSON('http://myapi.com');
showResults(results);

3.

let sum = calculateSum(2, 6);
if (sum > 8) {
    console.log('larger than 8');
}

4.

let data = $.getJSON('http://myapi.com');
data = data.map(function (x) { return x * 8; });

writeDataToFile(data);

• Create at least 2 issues (bug / feature / code improvement) on another teams github repository. Do this in pairs.
• Solve the issue proposed by another students in your github repo. More info here

You will complete the TicTacToe game we started building in class. The code we build in class is available here: https://github.com/HackYourFuture/TicTacToeTDD. One of your teammates should fork the above repo. Work in this repository together so you can see who wrote which code. Make a Pull Request to hand in this part of the homework.

Upload your homework in your "hyf-javascript3" Github repository. Make sure to create a new folder "week3" first. Upload your homework files inside the week3 folder and write a description for this “commit”. Your hyf-javascript3/week3 should now contain all your homework files. Place the link to your repository folder in Trello.