JSFiddle - React, Tailwind, and code Playground

HTML

<div id='v1'></div>
<div id='v2'></div>

JavaScript

function Ctor(value) {
    if (!(this instanceof Ctor)) {
        return new Ctor(value); 
    }

    this.value = value;
}

var v1instance = Ctor('v1');
// Juan: Who expects this to work? Not me... :)

var v2instance = Ctor.call(v1instance, 'v2');

// Expected v1, got v2
// Juan: You got v2 because your call to Ctor.call(v1instance, 'v2') 
// Juan: What else would you expect?, for v2 to get thrown away?
document.getElementById('v1').innerHTML = (v1instance !== undefined) ? v1instance.value : 'No value';

// Expected v2, got No value
// Juan: You didn't call the constructor
document.getElementById('v2').innerHTML = (v2instance !== undefined) ? v2instance.value : 'No value';