Skip to main content

Decorator to prevent base class methods from being called directly.

Project description

Decorator to prevent base class methods from being called directly.

Usage

from virtualmethod import virtualmethod

class Base(object):
    @virtualmethod
    def my_virtual_method(self):
        print "This is a virtual method. Call me from a subclass!"

class A(Base):
    pass

class B(Base):
    def my_virtual_method(self):
        print "I went ahead and implemented my own version."

base = Base()
a = A()
b = B()

a.my_virtual_method()
-> This is a virtual method. Call me from a subclass!

b.my_virtual_method()
-> I went ahead and implemented my own version.

base.my_virtual_method()
-> Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "virtualmethod/core.py", line 11, in __call__
    raise TypeError("Virtual method %s must be called from a subclass." % self.__name__)
TypeError: Virtual method my_virtual_method must be called from a subclass.

Note(s)

@virtualmethod works with @classmethod and @staticmethod, but must be declared first, i.e.:

@virtualmethod
@classmethod
def my_virtual_class_method(cls):
    ...

Credit

Thanks to Patrick Hensley for his input, and to Denis Ryzhkov for his method_decorator module.

Project details


Download files

Download the file for your platform. If you're not sure which to choose, learn more about installing packages.

Source Distribution

virtualmethod-0.0.1.tar.gz (3.5 kB view hashes)

Uploaded Source

Supported by

AWS AWS Cloud computing and Security Sponsor Datadog Datadog Monitoring Fastly Fastly CDN Google Google Download Analytics Microsoft Microsoft PSF Sponsor Pingdom Pingdom Monitoring Sentry Sentry Error logging StatusPage StatusPage Status page