JSFiddle - React, Tailwind, and code Playground

JavaScript

var CallBack;
for(var i=0;i<3;i++){
    (function(i) {
        var Proof = true
        if (i == 0){
            Proof = false
            //var CallBack = function(){alert(Proof);}; // true????
            CallBack = function(){alert(i);};
        }
    })(i);
}

CallBack()