def isnamedtupleinstance(x):
t = type(x)
b = t.__bases__
if len(b) != 1 or b[0] != tuple: return False
f = getattr(t, '_fields', None)
if not isinstance(f, tuple): return False
return all(type(n)==str for n in f)
有可能从中得到误报，但前提是有人不遗余力地创建一种看起来很多像命名元组但不是一个；-)。
Calling the functioncollections.namedtuple gives you a new type that's a subclass of tuple (and no other classes) with a member named _fields that's a tuple whose items are all strings. So you could check for each and every one of these things:
def isnamedtupleinstance(x):
t = type(x)
b = t.__bases__
if len(b) != 1 or b[0] != tuple: return False
f = getattr(t, '_fields', None)
if not isinstance(f, tuple): return False
return all(type(n)==str for n in f)
it IS possible to get a false positive from this, but only if somebody's going out of their way to make a type that looks a lot like a named tuple but isn't one;-).
If you need to check before calling namedtuple specific functions on it, then just call them and catch the exception instead. That's the preferred way to do it in python.
def isinstance_namedtuple(x):
return (isinstance(x, tuple) and
isinstance(getattr(x, '__dict__', None), collections.Mapping) and
getattr(x, '_fields', None) is not None)
Improving on what Lutz posted:
def isinstance_namedtuple(x):
return (isinstance(x, tuple) and
isinstance(getattr(x, '__dict__', None), collections.Mapping) and
getattr(x, '_fields', None) is not None)
isinstance(x, tuple) and isinstance(x.__dict__, collections.abc.Mapping)
which to me appears to best reflect the dictionary aspect of the nature of named tuples.
It appears robust against some conceivable future changes too and might also work with many third-party namedtuple-ish classes, if such things happen to exist.
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调用函数
collections.namedtuple会为您提供一个新类型，它是tuple的子类（并且没有其他类），并且具有名为的成员_fields这是一个元组，其项目都是字符串。因此，您可以检查每一项：有可能从中得到误报，但前提是有人不遗余力地创建一种看起来很多像命名元组但不是一个；-)。
Calling the function
collections.namedtuplegives you a new type that's a subclass oftuple(and no other classes) with a member named_fieldsthat's a tuple whose items are all strings. So you could check for each and every one of these things:it IS possible to get a false positive from this, but only if somebody's going out of their way to make a type that looks a lot like a named tuple but isn't one;-).
如果你想确定一个对象是否是特定namedtuple的实例，你可以这样做：
If you want to determine whether an object is an instance of a specific namedtuple, you can do this:
3.7+
3.7+
如果您需要在调用namedtuple特定函数之前进行检查，那么只需调用它们并捕获异常即可。这是在 python 中执行此操作的首选方法。
If you need to check before calling namedtuple specific functions on it, then just call them and catch the exception instead. That's the preferred way to do it in python.
改进 Lutz 发布的内容：
Improving on what Lutz posted:
在我看来，我使用
的似乎最能反映命名元组性质的字典方面。
它对于一些可以想象的未来变化似乎也很强大，并且也可能与许多第三方命名元组类一起使用，如果这样的事情碰巧存在的话。
I use
which to me appears to best reflect the dictionary aspect of the nature of named tuples.
It appears robust against some conceivable future changes too and might also work with many third-party namedtuple-ish classes, if such things happen to exist.
IMO 这可能是 Python 3.6 及更高版本的最佳解决方案。
您可以在实例化命名元组时设置自定义
__module__，稍后检查它，然后检查
__module__if getattr(x, "__module__", None) = =“xxxx.命名空间”：IMO this might be the best solution for Python 3.6 and later.
You can set a custom
__module__when you instantiate your namedtuple, and check for it laterthen check for
__module__if getattr(x, "__module__", None) == "xxxx.namespace":