Is it possible to have static methods in Python which I could call without initializing a class, like:
ClassName.static_method()
Answer
Yep, using the staticmethod decorator
class MyClass(object):
@staticmethod
def the_static_method(x):
print(x)
MyClass.the_static_method(2) # outputs 2
Note that some code might use the old method of defining a static method, using staticmethod
as a function rather than a decorator. This should only be used if you have to support ancient versions of Python (2.2 and 2.3)
class MyClass(object):
def the_static_method(x):
print(x)
the_static_method = staticmethod(the_static_method)
MyClass.the_static_method(2) # outputs 2
This is entirely identical to the first example (using @staticmethod
), just not using the nice decorator syntax
Finally, use staticmethod()
sparingly! There are very few situations where static-methods are necessary in Python, and I've seen them used many times where a separate "top-level" function would have been clearer.
The following is verbatim from the documentation::
A static method does not receive an implicit first argument. To declare a static method, use this idiom:
class C:
@staticmethod
def f(arg1, arg2, ...): ...
The @staticmethod form is a function decorator – see the description of function definitions in Function definitions for details.
It can be called either on the class (such as
C.f()
) or on an instance (such asC().f()
). The instance is ignored except for its class.
Static methods in Python are similar to those found in Java or C++. For a more advanced concept, see
classmethod()
.
For more information on static methods, consult the documentation on the standard type hierarchy in The standard type hierarchy.
New in version 2.2.
Changed in version 2.4: Function decorator syntax added.
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