python标准库中的装饰器（@deprecated） |
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这是另一种解决方案： 该装饰器（实际上是装饰器工厂）允许您提供原因消息。通过提供源文件名和行号来帮助开发人员诊断问题也更有用。 编辑：此代码使用Zero的建议：用替换warnings.warn_explicit行warnings.warn(msg, category=DeprecationWarning, stacklevel=2)，它打印函数调用站点而不是函数定义站点。它使调试更加容易。 EDIT2：此版本允许开发人员指定可选的“原因”消息。 import functools import inspect import warnings string_types = (type(b''), type(u'')) def deprecated(reason): """ This is a decorator which can be used to mark functions as deprecated. It will result in a warning being emitted when the function is used. """ if isinstance(reason, string_types): # The @deprecated is used with a 'reason'. # # .. code-block:: python # # @deprecated("please, use another function") # def old_function(x, y): # pass def decorator(func1): if inspect.isclass(func1): fmt1 = "Call to deprecated class {name} ({reason})." else: fmt1 = "Call to deprecated function {name} ({reason})." @functools.wraps(func1) def new_func1(*args, **kwargs): warnings.simplefilter('always', DeprecationWarning) warnings.warn( fmt1.format(name=func1.__name__, reason=reason), category=DeprecationWarning, stacklevel=2 ) warnings.simplefilter('default', DeprecationWarning) return func1(*args, **kwargs) return new_func1 return decorator elif inspect.isclass(reason) or inspect.isfunction(reason): # The @deprecated is used without any 'reason'. # # .. code-block:: python # # @deprecated # def old_function(x, y): # pass func2 = reason if inspect.isclass(func2): fmt2 = "Call to deprecated class {name}." else: fmt2 = "Call to deprecated function {name}." @functools.wraps(func2) def new_func2(*args, **kwargs): warnings.simplefilter('always', DeprecationWarning) warnings.warn( fmt2.format(name=func2.__name__), category=DeprecationWarning, stacklevel=2 ) warnings.simplefilter('default', DeprecationWarning) return func2(*args, **kwargs) return new_func2 else: raise TypeError(repr(type(reason)))您可以将此修饰符用于函数，方法和类。 这是一个简单的例子： @deprecated("use another function") def some_old_function(x, y): return x + y class SomeClass(object): @deprecated("use another method") def some_old_method(self, x, y): return x + y @deprecated("use another class") class SomeOldClass(object): pass some_old_function(5, 3) SomeClass().some_old_method(8, 9) SomeOldClass()你会得到： deprecated_example.py:59: DeprecationWarning: Call to deprecated function or method some_old_function (use another function). some_old_function(5, 3) deprecated_example.py:60: DeprecationWarning: Call to deprecated function or method some_old_method (use another method). SomeClass().some_old_method(8, 9) deprecated_example.py:61: DeprecationWarning: Call to deprecated class SomeOldClass (use another class). SomeOldClass()EDIT3：现在，此装饰器已成为不推荐使用的库的一部分： Python包索引（PyPi） GitHub网站 阅读文档 推特新的稳定版本v1.2.10🎉 |
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