JSFiddle - React, Tailwind, and code Playground

JavaScript

var pouet = "pouet";

function afficheMoiNawak() {
    var pasPouet = "pasPouet";
    if(typeof(pouet) != "undefined") {
        alert("1 : "+pouet);
    }
    if(typeof(pasPouet) != "undefined") {
        alert("2 : "+pasPouet);
    }
}

if(typeof(pasPouet) != "undefined") {
    alert("3 : "+pasPouet);
}

afficheMoiNawak();