old_contents: var basic   = require('../../lib/index'),
      http    = require('http');
  
  
  var auth    = basic(function (user, pass, callback) {
      if (user === 'let' && pass === 'me in') return callback(null);
      callback(401);
  });
  
  http.createServer(function (req, res) {
      auth(req, res, function (err) {
          if (err) {
              res.writeHead(err);
              res.end();
          }
  
          res.writeHead(200);
          res.end();
      });
  }).listen(8000);
new_contents: var basic   = require('../../lib/index'),
      http    = require('http');
  
  
  var auth    = basic(function (user, pass, callback) {
      if (user === 'let' && pass === 'me in') return callback(null);
      callback(401);
  });
  
  http.createServer(function (req, res) {
      auth(req, res, function (err) {
          res.writeHead(err || 200);
          res.end();
      });
  }).listen(8000);
subject: Update example