Boolean coercion

Use !! to see how JavaScript would coerce a real value into a boolean-ish interpretation.

console.log(!!" ") // true
console.log(!!"")  //  false
console.log(!!"0") //  true
console.log(!!0) //  false

Comments

[Nurullo]

Heya, actually the last expression console.log(!!"0") should be true not false :)

[icncsx]

You're absolutely right. I meant to say !!0 :)