code: function next() {
    var limireq = this;
    var conn = limireq.connections.shift()
    if (!conn) return
  
    request(conn.options, function(err, res, body) {
      if (typeof conn.callback === 'function')
        conn.callback(err, res, body)
      else
        limireq.emit('data', err, res, body)
  
      // Signal the end of processing
      if (++limireq.completed === limireq.total) {
        limireq.active = false
        limireq.emit('end')
      } else next.call(limireq)
    })
  }
docs: Don't expose this function to the public prototype