--- id: a77dbc43c33f39daa4429b4f title: Boo who challengeType: 1 forumTopicId: 16000 dashedName: boo-who --- # --description-- Check if a value is classified as a boolean primitive. Return `true` or `false`. Boolean primitives are `true` and `false`. # --hints-- `booWho(true)` should return `true`. ```js assert.isTrue(booWho(true)); ``` `booWho(false)` should return `true`. ```js assert.isTrue(booWho(false)); ``` `booWho([1, 2, 3])` should return `false`. ```js assert.isFalse(booWho([1, 2, 3])); ``` `booWho([].slice)` should return `false`. ```js assert.isFalse(booWho([].slice)); ``` `booWho({ "a": 1 })` should return `false`. ```js assert.isFalse(booWho({ a: 1 })); ``` `booWho(1)` should return `false`. ```js assert.isFalse(booWho(1)); ``` `booWho(NaN)` should return `false`. ```js assert.isFalse(booWho(NaN)); ``` `booWho("a")` should return `false`. ```js assert.isFalse(booWho('a')); ``` `booWho("true")` should return `false`. ```js assert.isFalse(booWho('true')); ``` `booWho("false")` should return `false`. ```js assert.isFalse(booWho('false')); ``` # --seed-- ## --seed-contents-- ```js function booWho(bool) { return bool; } booWho(null); ``` # --solutions-- ```js function booWho(bool) { return typeof bool === 'boolean'; } booWho(null); ```