JavaScript: calling the grandparent's constructor

ugly.js

// Note: You wouldn't ever want to do this!

function A () {
	this.a = true
	return this
}
A.prototype.fromA = 'from A'

function B () {
	this.constructor.prototype.__proto__.constructor.call(this)
	this.b = true
	return this
}
B.prototype = Object.create(A.prototype)
B.prototype.constructor = B
B.prototype.fromB = 'from B'

function C () {
  // By using __proto__.__proto__, we're skipping B:
	this.constructor.prototype.__proto__.__proto__.constructor.call(this)
	this.c = true
	return this
}
C.prototype = Object.create(B.prototype)
C.prototype.constructor = C
C.prototype.fromC = 'from C'

new C()
// C { a: true, c: true }
(new C()).fromB
// 'from B'