如何修复Godot GDScript中‘类文件中不允许使用自身类名’错误？

错误原因 #

在Player类的全局作用域里直接用Player.new()创建实例时，类还没完成定义，Godot禁止这种在类自身未加载完成时引用类名实例化的操作，所以触发了错误。

可行解决方法 #

• 延迟实例化到生命周期函数：把创建实例的代码放到_ready()函数中，这时类已经完全加载完成，可以正常引用类名：

  class_name Player
  var player: Player # 先声明变量类型
  var player_seed = ""
  
  func _ready():
      player = Player.new() # 在_ready中完成实例化
  
  func _on_Button_pressed():
      var new_seed = int($ColorRect/LineEdit.text)
      player.player_seed = new_seed
  

• 用self替代类名实例化：如果是要创建当前类的实例，也可以用self.new()代替Player.new()，同样建议放到_ready()中执行：

  class_name Player
  var player: Player
  var player_seed = ""
  
  func _ready():
      player = self.new()
  
  func _on_Button_pressed():
      var new_seed = int($ColorRect/LineEdit.text)
      player.player_seed = new_seed
  

• 无需额外实例化的优化方案：如果你的需求只是修改当前对象的player_seed，根本不需要创建新的Player实例，直接修改当前对象的属性即可：

  class_name Player
  var player_seed = ""
  
  func _on_Button_pressed():
      var new_seed = int($ColorRect/LineEdit.text)
      player_seed = new_seed # 等价于 self.player_seed = new_seed
  

内容的提问来源于stack exchange，提问作者Inchy