Function getIndexRoute

docs/lib/ReactRouter.js:4177–4206

(route, location, callback)

	}

	function getIndexRoute(route, location, callback) {
	  if (route.indexRoute) {
	    callback(null, route.indexRoute);
	  } else if (route.getIndexRoute) {
	    route.getIndexRoute(location, function (error, indexRoute) {
	      callback(error, !error && _RouteUtils.createRoutes(indexRoute)[0]);
	    });
	  } else if (route.childRoutes) {
	    (function () {
	      var pathless = route.childRoutes.filter(function (obj) {
	        return !obj.hasOwnProperty('path');
	      });

	      _AsyncUtils.loopAsync(pathless.length, function (index, next, done) {
	        getIndexRoute(pathless[index], location, function (error, indexRoute) {
	          if (error || indexRoute) {
	            var routes = [pathless[index]].concat(Array.isArray(indexRoute) ? indexRoute : [indexRoute]);
	            done(error, routes);
	          } else {
	            next();
	          }
	        });
	      }, function (err, routes) {
	        callback(null, routes);
	      });
	    })();
	  } else {
	    callback();
	  }
	}

	function assignParams(params, paramNames, paramValues) {
	  return paramNames.reduce(function (params, paramName, index) {