JSFiddle - React, Tailwind, and code Playground

JavaScript

//Closure---
var aFunction = function(i){
 alert(i);
}

/* for ( var i = 0; i < 5; i++ ) {
    setTimeout(new aFunction(i), i * 100 );
} */

for ( var i = 0; i < 5; i++ ) {
  setTimeout(function() {
       alert( i );
    }, i * 100 );
}