add: if (file == null) {file = name} 
context:   Macro: function (name,file) {    var macro = jsMath.Parser.prototype.macros;    macro[name] = ['Extension',file];  },
meta: 7708	/local1/tlutelli/issta_data/temp/all_js/javascript/2006_temp/2006/7708/a844e1ec626c2b970c32377c4ad06bb088afa9bd/jsMath.js/buggy/htdocs/jsMath/uncompressed/jsMath.js