Ext.extend(Ext.data.JsonReader, Ext.data.DataReader, {
    /**
     * This JsonReader's metadata as passed to the constructor, or as passed in
     * the last data packet's <b><tt>metaData</tt></b> property.
     * @type Mixed
     * @property meta
     */
    /**
     * This method is only used by a DataProxy which has retrieved data from a remote server.
     * @param {Object} response The XHR object which contains the JSON data in its responseText.
     * @return {Object} data A data block which is used by an Ext.data.Store object as
     * a cache of Ext.data.Records.
     */
    read : function(response){
        var json = response.responseText;
        var o = Ext.decode(json);
        if(!o) {
            throw {message: "JsonReader.read: Json object not found"};
        }
        return this.readRecords(o);
    }

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Ext.util.JSON = new (function(){
    var useHasOwn = !!{}.hasOwnProperty,
        isNative = function() {
            var useNative = null;

            return 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 + ')');    
        }

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