code: function _compressOther(json, aKeys) {
      var oKeys,
        aKey,
        str,
        nLenKeys,
        nIndex,
        obj;
      aKeys = _getKeys(json, aKeys);
      aKeys = unique(aKeys);
      oKeys = _biDimensionalArrayToObject(aKeys);
  
      str = JSON.stringify(json);
      nLenKeys = aKeys.length;
  
      for (nIndex = 0; nIndex < nLenKeys; nIndex++) {
        aKey = aKeys[nIndex];
        str = str.replace(new RegExp(escapeRegExp('"' + aKey[1] + '"'), 'g'), '"' + aKey[0] + '"');
      }
      obj = JSON.parse(str);
      obj._ = oKeys;
      return obj;
    }
docs: Method to compress anything but array
  @private
  @param json
  @param aKeys
  @returns {*}