rem: return; 
add: return null; 
context: function rdf_duassert (n1, a, n2){    var oldN2 = this.ds.GetTarget (n1, a, true);    if (!oldN2)    {        dd ("** Unable to change " + n1.Value + " -[" + a.Value + "]->, " +            "because old value was not found.");        return;    }        return this.ds.Change (n1, a, oldN2, n2);    }
meta: 5459	/local1/tlutelli/issta_data/temp/all_js/javascript/2006_temp/2006/5459/bc4c96a140926ec86fe50356080fff32b2697cd5/rdf.js/clean/extensions/irc/xul/content/rdf.js