DI v.1

di.js

var binds = {
    'SquareCalc': ['Multiplicator'],
    'A': ['SquareCalc'],
    'B': ['Multiplicator']
};

var registry = {};

function make(cls) {
    if (registry[cls]) {
        return registry[cls]
    }
    var deps = [null];
    for (var i in binds[cls]) {
        deps.push(make(binds[cls][i]));
    }
    var instance = new (Function.prototype.bind.apply(window[cls], deps));
    registry[cls] = instance;
    return instance;
}

function Calc() {
    this.plus = function(a, b) {
        return +a + +b
    }
}

function SquareCalc(multi) {
    this.multi = multi;
    this.plus = function(a, b) {
        return multi.run(a) + multi.run(b)
    }
}

function Multiplicator() {
    this.run = function(a) {
        return a * a;
    }
}

function A(calc) {
    this.calc = calc;
}
function B() {}

var a = make('A');
var b = make('B');

a.calc.plus(10, 20)