How to use the rdf-ext.setPrefix function in rdf-ext

},{}],"rdf2h":[function(require,module,exports){
/* global rdf, Mustache */


var rdf = require("rdf-ext");
var clownface = require("clownface");
var Mustache = require("mustache");
var Logger = require("./logger.js");
var NodeSet = require("./node-set.js");

rdf.setPrefix("r2h", "http://rdf2h.github.io/2015/rdf2h#");

function RDF2h(matcherGraph) {
    RDF2h.logger.info("To see more debug output invoke RDF2h.logger.setLevel(Logger.DEBUG) or even RDF2h.logger.setLevel(Logger.TRACE)");
    this.matcherGraph = matcherGraph;
    var unorderedMatchers = new NodeSet();
    var rdfTypeProperty = rdf.createNamedNode("http://www.w3.org/1999/02/22-rdf-syntax-ns#type");
    var matcherType = rdf.createNamedNode("http://rdf2h.github.io/2015/rdf2h#Matcher");
    var matcherStatements = matcherGraph.match(null, rdfTypeProperty, matcherType);
    matcherStatements.forEach(function(t) {
        unorderedMatchers.add(t.subject);
    });
    /*Sorting:
     * 
     * Choose any matcher that is not the object of any before statement . 
     * Remove all before statements with that matcher as subject. 
     * Repeat till there are no more matchers that are not the object of a