    /**
     * Modified version of [Douglas Crockford's JSON.js][dc] that doesn't
     * mess with the Object prototype.
     *
     * [dc]: http://www.json.org/js.html
     *
     * @singleton
     */
    Ext.JSON = (new(function() {
        var me = this,
        encodingFunction,
        decodingFunction,
        useNative = null,
        useHasOwn = !! {}.hasOwnProperty,
        isNative = function() {
            if (useNative === null) {
                useNative = Ext.USE_NATIVE_JSON && window.JSON && JSON.toString() == '[object JSON]';
            }
            return useNative;
        },
        pad = function(n) {
            return n < 10 ? "0" + n : n;
        },
        doDecode = function(json) {
            return eval("(" + json + ')');
        },
        doEncode = function(o, newline) {
            // http://jsperf.com/is-undefined
            if (o === null || o === undefined) {
                return "null";
            } else if (Ext.isDate(o)) {
                return Ext.JSON.encodeDate(o);
            } else if (Ext.isString(o)) {
                return Ext.JSON.encodeString(o);
            } else if (typeof o == "number") {
                //don't use isNumber here, since finite checks happen inside isNumber
                return isFinite(o) ? String(o) : "null";
            } else if (Ext.isBoolean(o)) {
                return String(o);
            }
            // Allow custom zerialization by adding a toJSON method to any object type.
            // Date/String have a toJSON in some environments, so check these first.
            else if (o.toJSON) {
                return o.toJSON();
            } else if (Ext.isArray(o)) {
                return encodeArray(o, newline);
            } else if (Ext.isObject(o)) {
                return encodeObject(o, newline);
            } else if (typeof o === "function") {
                return "null";
            }
            return 'undefined';
        },
        m = {
            "\b": '\\b',
            "\t": '\\t',
            "\n": '\\n',
            "\f": '\\f',
            "\r": '\\r',
            '"': '\\"',
            "\\": '\\\\',
            '\x0b': '\\u000b' //ie doesn't handle \v
        },
        charToReplace = /[\\\"\x00-\x1f\x7f-\uffff]/g,
        encodeString = function(s) {
            return '"' + s.replace(charToReplace, function(a) {
                var c = m[a];
                return typeof c === 'string' ? c : '\\u' + ('0000' + a.charCodeAt(0).toString(16)).slice(-4);
            }) + '"';
        },

        //<debug>
        encodeArrayPretty = function(o, newline) {
            var len = o.length,
                cnewline = newline + '   ',
                sep = ',' + cnewline,
                a = ["[", cnewline], // Note newline in case there are no members
                i;

            for (i = 0; i < len; i += 1) {
                a.push(Ext.JSON.encodeValue(o[i], cnewline), sep);
            }

            // Overwrite trailing comma (or empty string)
            a[a.length - 1] = newline + ']';

            return a.join('');
        },

        encodeObjectPretty = function(o, newline) {
            var cnewline = newline + '   ',
                sep = ',' + cnewline,
                a = ["{", cnewline], // Note newline in case there are no members
                i;

            for (i in o) {
                if (!useHasOwn || o.hasOwnProperty(i)) {
                    a.push(Ext.JSON.encodeValue(i) + ': ' + Ext.JSON.encodeValue(o[i], cnewline), sep);
                }
            }

            // Overwrite trailing comma (or empty string)
            a[a.length - 1] = newline + '}';

            return a.join('');
        },
        //</debug>

        encodeArray = function(o, newline) {
            //<debug>
            if (newline) {
                return encodeArrayPretty(o, newline);
            }
            //</debug>

            var a = ["[", ""], // Note empty string in case there are no serializable members.
                len = o.length,
                i;
            for (i = 0; i < len; i += 1) {
                a.push(Ext.JSON.encodeValue(o[i]), ',');
            }
            // Overwrite trailing comma (or empty string)
            a[a.length - 1] = ']';
            return a.join("");
        },

        encodeObject = function(o, newline) {
            //<debug>
            if (newline) {
                return encodeObjectPretty(o, newline);
            }
            //</debug>

            var a = ["{", ""], // Note empty string in case there are no serializable members.
                i;
            for (i in o) {
                if (!useHasOwn || o.hasOwnProperty(i)) {
                    a.push(Ext.JSON.encodeValue(i), ":", Ext.JSON.encodeValue(o[i]), ',');
                }
            }
            // Overwrite trailing comma (or empty string)
            a[a.length - 1] = '}';
            return a.join("");
        };

        /**
         * Encodes a String. This returns the actual string which is inserted into the JSON string as the literal
         * expression. **The returned value includes enclosing double quotation marks.**
         *
         * To override this:
         *
         *     Ext.JSON.encodeString = function(s) {
         *         return 'Foo' + s;
         *     };
         *
         * @param {String} s The String to encode
         * @return {String} The string literal to use in a JSON string.
         * @method
         */
        me.encodeString = encodeString;

        /**
         * The function which {@link #encode} uses to encode all javascript values to their JSON representations
         * when {@link Ext#USE_NATIVE_JSON} is `false`.
         *
         * This is made public so that it can be replaced with a custom implementation.
         *
         * @param {Object} o Any javascript value to be converted to its JSON representation
         * @return {String} The JSON representation of the passed value.
         * @method
         */
        me.encodeValue = doEncode;

        /**
         * Encodes a Date. This returns the actual string which is inserted into the JSON string as the literal
         * expression. **The returned value includes enclosing double quotation marks.**
         *
         * The default return format is `"yyyy-mm-ddThh:mm:ss"`.
         *
         * To override this:
         *
         *     Ext.JSON.encodeDate = function(d) {
         *         return Ext.Date.format(d, '"Y-m-d"');
         *     };
         *
         * @param {Date} d The Date to encode
         * @return {String} The string literal to use in a JSON string.
         */
        me.encodeDate = function(o) {
            return '"' + o.getFullYear() + "-"
            + pad(o.getMonth() + 1) + "-"
            + pad(o.getDate()) + "T"
            + pad(o.getHours()) + ":"
            + pad(o.getMinutes()) + ":"
            + pad(o.getSeconds()) + '"';
        };

        /**
         * Encodes an Object, Array or other value.
         *
         * If the environment's native JSON encoding is not being used ({@link Ext#USE_NATIVE_JSON} is not set,
         * or the environment does not support it), then ExtJS's encoding will be used. This allows the developer
         * to add a `toJSON` method to their classes which need serializing to return a valid JSON representation
         * of the object.
         *
         * @param {Object} o The variable to encode
         * @return {String} The JSON string
         */
        me.encode = function(o) {
            if (!encodingFunction) {
                // setup encoding function on first access
                encodingFunction = isNative() ? JSON.stringify : me.encodeValue;
            }
            return encodingFunction(o);
        };

        /**
         * Decodes (parses) a JSON string to an object. If the JSON is invalid, this function throws
         * a SyntaxError unless the safe option is set.
         *
         * @param {String} json The JSON string
         * @param {Boolean} [safe=false] True to return null, false to throw an exception if the JSON is invalid.
         * @return {Object} The resulting object
         */
        me.decode = function(json, safe) {
            if (!decodingFunction) {
                // setup decoding function on first access
                decodingFunction = isNative() ? JSON.parse : doDecode;
            }
            try {
                return decodingFunction(json);
            } catch (e) {
                if (safe === true) {
                    return null;
                }
                Ext.Error.raise({
                    sourceClass: "Ext.JSON",
                    sourceMethod: "decode",
                    msg: "You're trying to decode an invalid JSON String: " + json
                });
            }
        };
    })());
    /**
     * Shorthand for {@link Ext.JSON#encode}
     * @member Ext
     * @method encode
     * @inheritdoc Ext.JSON#encode
     */
    Ext.encode = Ext.JSON.encode;
    /**
     * Shorthand for {@link Ext.JSON#decode}
     * @member Ext
     * @method decode
     * @inheritdoc Ext.JSON#decode
     */
    Ext.decode = Ext.JSON.decode;