rem: rv += p + ", "; 
add: rv += rv ? ", " + p : p; 
context: function keys (o){    var rv = "";        for (var p in o)        rv += p + ", ";    return rv;    }
meta: 1567	/local1/tlutelli/issta_data/temp/all_js/javascript/2006_temp/2006/1567/662cf7664d92e40424a13e6384343ea23a2fa8a8/utils.js/clean/js/lib/utils.js