What does = +_ mean in JavaScript

Question

I was wondering what the = +_ operator means in JavaScript. It looks like it does assignments.

Example:

hexbin.radius = function(_)         


        

Answer 1

+_ is almost equivalent of parseFloat(_) . Observe that parseInt will stop at non numeric character such as dot, whereas parshFloat will not.

EXP:

    parseFloat(2.4) = 2.4 
vs 
    parseInt(2.4) = 2 
vs 
    +"2.4" = 2.4

Exp:

var _ = "3";
    _ = +_;

console.log(_); // will show an integer 3

Very few differences:

• Empty string "" evaluates to a 0, while parseInt() evaluates to NaN
• For more info look here: parseInt vs unary plus - when to use which