rem: var newItem = aItem.clone(); newItem.generation += 1; newItem.makeImmutable(); this.mItems[newItem.id] = newItem; 
add: var modifiedItem = aNewItem.clone(); modifiedItem.generation += 1; modifiedItem.makeImmutable(); this.mItems[newItem.id] = modifiedItem; 
context:     modifyItem: function (aItem, aListener) {        if (aItem.id == null ||            this.mItems[aItem.id] == null)        {            // this is definitely an error            if (aListener)                aListener.onOperationComplete (this.calendarToReturn,                                               Components.results.NS_ERROR_FAILURE,                                               aListener.MODIFY,                                               aItem.id,                                               "ID for modifyItem doesn't exist, is null, or is from different calendar");            return;        }        var oldItem = this.mItems[aItem.id];        if (oldItem.generation != aItem.generation) {            if (aListener)                aListener.onOperationComplete (this.calendarToReturn,                                               Components.results.NS_ERROR_FAILURE,                                               aListener.MODIFY,                                               aItem.id,                                               "generation mismatch in modifyItem");            return;        }        var newItem = aItem.clone();        newItem.generation += 1;        newItem.makeImmutable();        this.mItems[newItem.id] = newItem;        if (aListener)            aListener.onOperationComplete (this.calendarToReturn,                                           Components.results.NS_OK,                                           aListener.MODIFY,                                           newItem.id,                                           newItem);        // notify observers        this.observeModifyItem(oldItem, newItem);    },
meta: 5459	/local1/tlutelli/issta_data/temp/all_js/javascript/2006_temp/2006/5459/f0c77cac48e7ce31af529637a1b48c03f4314901/calMemoryCalendar.js/clean/calendar/providers/memory/calMemoryCalendar.js