Class variables - Printable Version

Class variables - Printable Version

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Class variables - menator01 - Jun-04-2020

Given the scenario

class SomeClass:
    myvar = 0
    def __init__(self):
        do stuff here
    def func(self):
        do stuff here
        myvar += 1
        print(myvar)

Would not myvar be a global for the class?
I'm getting that it has not been assigned in the function.
Input much appreciated

RE: Class variables - Clunk_Head - Jun-04-2020

(Jun-04-2020, 12:53 PM)menator01 Wrote: Given the scenario
class SomeClass:
    myvar = 0
    def __init__(self):
        do stuff here
    def func(self):
        do stuff here
        myvar += 1
        print(myvar)
Would not myvar be a global for the class?
I'm getting that it has not been assigned in the function.
Input much appreciated

I'd say that you haven't received a reply because your question obfuscates your problem. You don't have an example of usage or any error code. That aside I have a bit of advise on your problem.

Class variables are accessed the same way that instance variables are accessed, that is by way of an instance.

class SomeClass:
    myvar = 0
    def __init__(self):
        do stuff here
    def func(self):
        do stuff here
        myvar += 1
        print(myvar)

my_instance = SomeClass()
print(my_instance.myvar) 
#Unlike some other languages class variables in python are not accessed by the class name

RE: Class variables - Yoriz - Jun-04-2020

Here is an example of accessing the class variable and the instance variable

class SomeClass:
    myvar = 0

    def __init__(self):
        self.myvar = 10

    def increase_class_variable(self):
        SomeClass.myvar += 1
        print(f'Shared class variable: {SomeClass.myvar}')

    def increase_instance_variable(self):
        self.myvar += 1
        print(f'Instance variable: {self.myvar}')


instance1 = SomeClass()
instance2 = SomeClass()
instance1.increase_class_variable()
instance1.increase_class_variable()
instance2.increase_class_variable()
instance1.increase_instance_variable()
instance1.increase_instance_variable()
instance2.increase_instance_variable()

Output:Shared class variable: 1
Shared class variable: 2
Shared class variable: 3
Instance variable: 11
Instance variable: 12
Instance variable: 11