What does + do here ?

Question

In a challenge, + is used but I don't know what's it is doing. I was something like this :

let a = 0.3;
console.log(a.toFixed(2)) // 0.30
console.log(+a.toFixed(2)) // 0.3

Is that a syntax commonly used, to put this + on its own ?
What is it doing exactly? Why does it remove one zero ?
https://code.sololearn.com/WQrtzOS2JS2b/?ref=app

Answer 1

+ here is the unary plus operator, which is often used in evaluating non-number values.
(+"304" === 304) // True

In your case it return a new number, with a 0 digit removed by JS floating point math, since the value returned by toFixed() is a string.

Answer 2

+ here is equivalent to function Number

console.log(Number(a.toFixed(2)))
https://code.sololearn.com/W4MxUr156k7k/?ref=app