clean JS prototyping

function A() {

}

var prot = A.prototype;
prot.a = function () {
	console.log('A::a()');
}


function B() {

}
B.prototype = A;

var prot = B.prototype;
prot.a = function () {
	prot.prototype.a.apply(this, arguments);
	console.log('B::b()');
};