JSFiddle - React, Tailwind, and code Playground

HTML

<input id="myinput" value="No name given" />
<button onclick="showPrompt();">Ask for the name</button>

JavaScript

window.showPrompt = function() {
    do {
        var name=prompt("Please enter your name");
    }
    while(name.length < 4);
    $('#myinput').val(name);
}