code: func StringOpen(l *State) int {
  	NewLibrary(l, stringLibrary)
  	l.CreateTable(0, 1)
  	l.PushString("")
  	l.PushValue(-2)
  	l.SetMetaTable(-2)
  	l.Pop(1)
  	l.PushValue(-2)
  	l.SetField(-2, "__index")
  	l.Pop(1)
  	return 1
  }
docs: // StringOpen opens the string library. Usually passed to Require.