JS Caching

gistfile1.js

var fibonacci = (function () {
    var cache = {};

    return function (n) {
        if (cache[n]) {
            return cache[n];
        }
        //console.log("Solving for " + n);

        var result;
        if (n < 1) {
            result = 0;
        }
        else if (n == 1) {
            result = 1;
        }
        else {
            // recursion
            result = fibonacci(n - 2) + fibonacci(n - 1);
        }

        cache[n] = result;
        return result;
    }
})();

for (var i = 0; i <= 20; i++) {
    console.log(i + ' -> ' + fibonacci(i));
}