javascript · level 1 · unit 4 · lesson 4
- meet it
- guess first
- your turn
- fix it
- nailed it
Tap a green word if you get lost.
meet it
Build bigger questions with &&, || !.
&& means and. It gives true only when both sides are true. A cake needs flour and eggs: if either one is missing, there is no cake.
|| means . It gives true when at least one side is true, like a lie-in on Saturday or Sunday. ! means : it flips an answer, so !true is false.
A box holding true or false already counts as a condition. So if (!hasEggs) reads like plain English: if we do not have eggs.
let hasFlour = true;
let hasEggs = false;
console.log(hasFlour && hasEggs);
console.log(hasFlour || hasEggs);
console.log(!hasEggs);Write a full condition on each side, like day === "Saturday" || day === "Sunday".
guess first
Did you earn pudding? Make a guess.
Guess before you run it. Wrong guesses are how you learn, and nothing is marked.
let atePeas = true;
let ateCarrots = true;
if (atePeas || ateCarrots) {
console.log("Pudding time!");
}your turn
Your turn. Get on the Twister.
The Twister has two rules: you must be 8 or older, and at least 120 cm tall. Choose an age and a height that get you on.
fix it
Since when are crisps healthy? Fix the check.
- Crisps are not an apple or a banana, yet it says healthy. Look at the right side of
||. "banana"on its own is not a question, and JavaScript counts it astrue. So theifalways runs.- Write the box name again:
snack === "apple" || snack === "banana", then press run.
nailed it
you can ask smarter questions now. :D
&&needs both sidestrue.||needs at least one.!flipstruetofalse, andfalsetotrue.- Write a full condition on each side of
&&or||.
new words in your collection
- and
- or
- not
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