允許在抽象類內使用用戶定義的裝飾器嗎？ 還是應該在繼承后使用它？

Question

例如，假設我有一個定義的裝飾器，稱為： decorate

def decorate(func):
  def inside_func(*args, **kwargs):
    # Do something
    return func(*args, **kwargs)
  return inside_func

接下來，假設我正在編寫一個名為Model的抽象類

from abc import ABC, abstractmethod

class Model(ABC):
  def __init__(self, value):
      self.value = value
      super().__init__()

  @abstractmethod
  @decorate # <-------------------- IS @decorate ALLOWED HERE?
  def do_something(self):
      pass

或者，應該是：

from abc import ABC, abstractmethod

class Model(ABC):
  def __init__(self, value):
    self.value = value
    super().__init__()

  @abstractmethod
  def do_something(self):
    pass

# Inherit the base class
class DoAdd42(Model):
   @decorate # <----------------------- SHOULD @decorate BE HERE INSTEAD?
   def do_something(self):
     return self.value + 42

如果兩者都允許，是否有“最佳實踐”方法？

Answer 1

兩者都允許。 因為abstractmethod ，您的decorate和類中的something都是函數。 您可以將它們打印到控制台進行驗證。

In [2]: def decorate(func):
   ...:   def inside_func(*args, **kwargs):
   ...:     # Do something
   ...:     return func(*args, **kwargs)
   ...:   return inside_func
   ...:
In [7]: from abc import ABC, abstractmethod
   ...:
   ...: class Model(ABC):
   ...:   def __init__(self, value):
   ...:       self.value = value
   ...:       super().__init__()
   ...:
   ...:   @abstractmethod
   ...:   @decorate # <-------------------- IS @decorate ALLOWED HERE?
   ...:   def do_something(self):
   ...:       pass
   ...:   # even no self is valid for class in Python3+
   ...:   def whatever():
   ...:       print('fff')
   ...:

In [8]: print(abstractmethod)
<function abstractmethod at 0x100ff86a8>

In [9]: print(Model.do_something)
<function decorate.<locals>.inside_func at 0x1041031e0>

In [10]: print(Model.whatever)
<function Model.whatever at 0x103b48950>

In [11]: Model.whatever()
fff

我對abstractmethod並不熟悉，所以我不了解最佳實踐以及有關其規則的更多詳細信息。 您可以根據我提供的信息並結合自己對abstractmethod的理解，嘗試做出自己的判斷。