rem: var arg = this.GetArgument(name); if (this.error) return null; 
add: var arg = this.GetArgument(name); if (this.error) {return null} 
context:   ProcessArg: function (name) {    var arg = this.GetArgument(name); if (this.error) return null;    return this.Process(arg);  },
meta: 1963	/local1/tlutelli/issta_data/temp/all_js/javascript/2006_temp/2006/1963/a844e1ec626c2b970c32377c4ad06bb088afa9bd/jsMath.js/clean/htdocs/jsMath/uncompressed/jsMath.js