get and set objects in localStorage and sessionStorage

StorageObject.js

// Forked from jfsiii https://gist.github.com/jfsiii/814784
// Forked from paul irish's https://gist.github.com/paulirish/601751
 
// desire: localStorage and sessionStorage should accept objects
//    in fact they do according to spec.
//    http://code.google.com/p/chromium/issues/detail?id=43666
 
// but so far that part isnt implemented anywhere.
 
// so we duckpunch set/getItem() to stringify/parse on the way in/out
// this seems to work in chrome 
//   but fails in FF (cant redefine setItem as a function, it just tostring's it)
// ^^^ Should be fixed now. Tested in FF 3.6 Mac OS X 10.6
// Fixed error with typeof == Number
 
// THIS IS INCOMPLETE CODE. would love any help if you'd like to help! :)
// Roger Raymond helped.
// John Schulz helped :)
// Christopher Castaneira helped :D
 
(function () {
 
    var toString = Object.prototype.toString,
        isArray = function (v) {
            return (/^\[object Array\]$/).test(toString.call(v));
        },
        isObject = function (v) {
            return (/^\[object Object\]$/).test(toString.call(v));
        };
 
    // Verifica sí get/setItem tienen soporte nativo para objetos
    var nativeJSONStorage = (function () {
        var feature_key = 'featureTest';
 
        if (!window.sessionStorage) return false;
        sessionStorage.setItem(feature_key, {});
 
        var item = sessionStorage.getItem(feature_key),
            bool = isObject(item) || isArray(item);
        sessionStorage.removeItem(feature_key);
 
        return bool;
    })();
    if (nativeJSONStorage) return;
 
    if (window.Storage) {
        var setter = Storage.prototype.setItem,
            getter = Storage.prototype.getItem;
 
        if (nativeJSONStorage) return;
 
        Storage.prototype.setItem = function (k, v) {
            var result;
 
            if (isObject(v) || isArray(v)) result = setter.call(this, k, JSON.stringify(v));
            else result = setter.apply(this, arguments);
 
            return result;
        };
 
        Storage.prototype.getItem = function (k) {
            var result = getter.apply(this, arguments);
 
            try {
                return JSON.parse(result);
            } catch (e) {
                return result;
            }
        };
    }
})();
 
 
// tests
console.group('localStorage');
localStorage.setItem('storage', {local:true});
console.log(localStorage.getItem('storage') && localStorage.getItem('storage').local == true);
console.groupEnd('localStorage');
 
console.group('sessionStorage');
sessionStorage.setItem('storage', {session: true});
console.log(sessionStorage.getItem('storage') && sessionStorage.getItem('storage').session == true);
console.groupEnd('sessionStorage');