code: func (sf StaticFile) AsStaticSocket() (ss StaticSocket, ok bool) {
  	if sf.b.ss.Type == "socket" {
  		return StaticSocket{sf}, true
  	}
  
  	return
  }
docs: // AsStaticSocket returns the StaticFile as a StaticSocket if the
  // StaticFile represents a socket. Otherwise, it returns the zero
  // value of StaticSocket and false.