Factorial function defined for n ∈ [0, 6]

gistfile1.js

var identity  = function (x) {
    return x;
};

var almost_factorial = function (f) {
    return function (n) {
        return (
            (0 === n)?
            1 :
            (n * f(n - 1)));
    };
};

var factorial6 =
    almost_factorial(
        almost_factorial(
            almost_factorial(
                almost_factorial(
                    almost_factorial(
                        almost_factorial(
                            almost_factorial(identity)))))));

var factorial = almost_factorial(factorial);

var show = function () {
    alert(factorial6(6));
};