// Pass through the invocation to the 'aspnet-prerendering' package, verifying that it can be loaded module.exports.renderToString = function (callback) { var aspNetPrerendering; try { aspNetPrerendering = require('aspnet-prerendering'); } catch (ex) { callback('To use prerendering, you must install the \'aspnet-prerendering\' NPM package.'); return; } return aspNetPrerendering.renderToString.apply(this, arguments); };