Truthy and Falsy

Truthy Falsy

👨‍💼 We often need to decide if a value "exists" without comparing it to null or undefined. JavaScript treats some values as falsy, and everything else as truthy.

Falsy values:

false
0, -0, 0n
'' (empty string)
null
undefined
NaN

You can convert any value to a boolean with Boolean(value) or !!value.

🐨 Open

index.ts

and:

Create hasUsername based on the truthiness of username
Create hasNickname based on the truthiness of nickname
Create hasAge based on the truthiness of age
Create hasNotes based on the truthiness of notes
Create canCheckout that's true when cartTotal is truthy and hasAcceptedTerms is true
Create canCreateAccount that's true when hasUsername, email, and password are all truthy

💰 Convert values to booleans when you need a strict true/false.

📜 MDN - Truthy 📜 MDN - Falsy

03. Primitive Types/06. Truthy and Falsy (💪 problem)

Truthy and Falsy