11-booleans

Lesson 11: Booleans & truthiness

true / false, and how non-booleans coerce.

What you'll learn

• falsy values: false, 0, '', null, undefined, NaN
• everything else is truthy — including [], {}, '0', 'false'
• use Boolean(x) or !!x to coerce explicitly
• guard with truthiness: if (user) { ... }

Example

See examples/.

Exercise

List which of 8 given values are truthy.