meet it

Put something new in a box and the old thing is gone.

Boxes made with let can change. Write the name, = and a new value, without let this time. The old value is thrown away. You can also copy one box into another.

Some boxes should never change, like your birthday. Make those with , short for constant. Try to change one and the checker stops you with TS2588.

+ can strings, end to end. "I feel " + mood sticks two strings into one. Leave a space inside the quotes, or the words will bump into each other.

let mood: string = "sleepy";
mood = "happy";
const birthday: string = "4 May";
console.log("I feel " + mood);
console.log("My birthday is " + birthday);

Use const for boxes that stay the same, and let for boxes you plan to change.

guess first

A copy, then a change. What is for lunch?

Guess before you run it. Wrong guesses are how you learn, and nothing is marked.

let snack: string = "crisps";
let lunch: string = snack;
snack = "grapes";
console.log(lunch);

your turn

Your turn. Change your mind.

Type a drink in the first blank and a different drink in the second. Then press run and watch the box change.

Your code

press run to see what happens

fix it

You scored again, but this will not run. Fix it!

Broken code to fix

press run to see what happens

Read the error: TS2588: Cannot assign to 'score' because it is a constant.
A box made with const can never change. This score needs to go up.
Change const to let on line 1, then press run.

nailed it

your boxes can change now. :D

Storing a new value replaces the old one.
const makes a box that can never change.
+ joins strings, so mind the spaces.

new words in your collection

const
join

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