SOURCE

function Super(){
    this.super = true;
}
function Sub(){
    this.sub =false;
}
Super.prototype.getSuperValue = function(){
    return this.super;
}
Sub.prototype = new Super()
Sub.prototype.getSubValue = function(){
    return this.sub
}
 let ins = new Sub()
 console.log(ins.getSubValue())
 console.log(ins.getSuperValue())
 console.log(ins instanceof Sub)
 console.log(ins instanceof Super)
 console.log(Object.getPrototypeOf(ins).constructor)