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Python: static class members

Static class member are possible in classes.

In order to create a static variable (aka class-variable) is created as part of the class statement by assigning a value to a variable. This variable then becomes the static data member.

In order to define a static method, the def statement needs to be prefixed with @staticmethod.

class C:

 #
 # Define a class variable (aka static member):
 #
   creation_counter = 0

   def __init__(self):

     #
     # increment
     #
       C.creation_counter += 1

     #
     # Assign a value to self.created which
     # effectively creates an instance variable:
     #
       self.created = C.creation_counter

 #
 # Define a static method. Note the «@staticmethod»
 #
   @staticmethod
   def printCreationCounter():
       print('The current value of creation_counter is {}'.format(C.creation_counter))

 #
 # Define an instance-method:
 #
   def printCreated(self):
       print('This instance has creation number {}'.format(self.created))


C.printCreationCounter()
#
#  The current value of creation_counter is 0


obj_1 = C()
obj_2 = C()

C.printCreationCounter()
#
# The current value of creation_counter is 2

obj_3 = C()


obj_3.printCreated()
#
# This instance has creation number 3

obj_1.printCreated()
#
# This instance has creation number 1

obj_2.printCreated()
#
# This instance has creation number 2

Github repository about-Python, path: /class/member/static.py

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