eRouter.js

eRouter = function(routes) {

  const run = function(routes) {

    let uri = window.location.hash;
    let params;

    if (uri.indexOf('#!/') === -1) return window.location.hash = '#!/';

    uri = uri.split('#!/').pop();

    if (!uri.length) return routes.index();

    if (uri.indexOf('/') > -1) {
      params = uri.split('/');
      uri = params.shift();
    }

    if (!routes[uri]) return routes.notFound(uri);

    routes[uri].apply(this, params);
  }

  this.set = (path) => window.location.hash = '#!/' + path;

  run(routes);

  window.addEventListener(
    'hashchange',
    run.bind(this, routes),
    false
  );
};