add: if (destKey < 0) destKey += len; 
context: function cycleView (amount){    var len = client.viewsArray.length;    if (len <= 1)        return;        var tb = getTabForObject (client.currentObject);    if (!tb)        return;        var vk = Number(tb.getAttribute("viewKey"));    var destKey = (vk + amount) % len; /* wrap around */        setCurrentObject (client.viewsArray[destKey].source);}
meta: 1567	/local1/tlutelli/issta_data/temp/all_js/javascript/2006_temp/2006/1567/be05be4e9e3ddc4d157924b6cfa3430d01b21eb1/static.js/buggy/xul/content/static.js