How Do Static Methods in Python Differ from Instance Methods, and How Are They Invoked?

Invoking Static Methods Directly from Class Instances

In Python, static methods provide an alternative approach to accessing class methods. They behave differently from instance methods in that they don't require instantiation and are accessible directly through the class itself.

Creation of Static Methods

To define a static method, the @staticmethod decorator is used. This decorator removes the self argument from the method signature, indicating that it's a static method. The following code example demonstrates this:

class MyClass(object):
    @staticmethod
    def the_static_method(x):
        print(x)

Invocation of Static Methods

Unlike instance methods, static methods can be invoked directly on the class instance or on the class itself. The following code snippets illustrate this behavior:

MyClass.the_static_method(2)  # outputs 2
MyClass().the_static_method(2)  # also outputs 2

Comparison with Legacy Static Method Definition

Older versions of Python (2.2 and 2.3) employed a different approach for defining static methods, using staticmethod as a function instead of a decorator. However, this is only necessary for maintaining compatibility with ancient Python implementations:

class MyClass(object):
    def the_static_method(x):
        print(x)
    the_static_method = staticmethod(the_static_method)

Sparing Use of Static Methods

It's important to note that static methods should be used sparingly. In most cases, separate top-level functions provide a clearer solution.

Official Documentation

The Python documentation describes static methods as follows:

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 as C().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_.

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