old_contents: var _ = require('lodash');
  
  /**
   * 格式化端口
   */
  module.exports = function () {
    var PORT = false;
  
    var portIndex = _.findIndex(process.argv, function (arg) {
      return arg === '-port' || arg === '-p';
    });
  
    if (portIndex !== -1 && _.isNumber(parseInt(process.argv[portIndex + 1], 10))) {
      PORT = process.argv[portIndex + 1];
    }
  
    var val = PORT || process.env.PORT || '3000';
    var port = parseInt(val, 10);
  
    if (isNaN(port)) {
      // named pipe
      return val;
    }
  
    if (port >= 0) {
      // port number
      return port;
    }
  
    return false;
  };
new_contents: var _ = require('lodash');
  
  /**
   * 格式化端口
   */
  module.exports = function () {
    var PORT = false;
  
    var portIndex = _.findIndex(process.argv, function (arg) {
      return arg === '--port' || arg === '-p';
    });
  
    if (portIndex !== -1 && _.isNumber(parseInt(process.argv[portIndex + 1], 10))) {
      PORT = process.argv[portIndex + 1];
    }
  
    var val = PORT || process.env.PORT || '3000';
    var port = parseInt(val, 10);
  
    if (isNaN(port)) {
      // named pipe
      return val;
    }
  
    if (port >= 0) {
      // port number
      return port;
    }
  
    return false;
  };
subject: add --port