callstack-example.js

var f = (e, t) => {
    return (5, 6) + 2;
}

var e = function () {
    return f(8,8) + 4;
}

window['a b'] = function () {
    return e(5, 7);
}

var c = function () {
    return window['a b'](7, 8);
}

var b = (e, t) => {
    return 456, c(5, 6) + 2;
}

function a() {
    return b(3, 4) + 3;
}

var res = a(1, 2) + 4;

console.log(res);