Originally Posted by python.noob

though i'm calling pr() function in the subclass after calling the get_details() function(which assigns value to name) it doesn't print the current value of name.

Originally Posted by lukerobi

Does this give you any insight?

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Python Syntax (Toggle Plain Text)

>>> class employee(object):
	def __init__(self):
		self.name = raw_input('Enter employee name: ')
 
 
>>> class calc(employee):
	def pr(self):
		print self.name
 
 
>>> d = calc()
Enter employee name: Bob
>>> d.pr()
Bob

>>> class employee(object): def __init__(self): self.name = raw_input('Enter employee name: ') >>> class calc(employee): def pr(self): print self.name >>> d = calc() Enter employee name: Bob >>> d.pr() Bob

Originally Posted by jlm699

Actually, it is printing the current value of name. The employee.name is always a space (' '), because you never change it. In your get_details function, you have created a new variable called name and assigned the users' input to it. Why don't you try printing x.name after your call to x.get_details()? You'll see that x.name is still just a blank space. The problem is that then name object that you're creating inside get_details only exists inside the scope of that function. You should be using self.name, which is the persistent attribute of the employee class. Let me demonstrate this principle:

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python Syntax (Toggle Plain Text)

>>> class no_init(object):
...     name = 'I have no init function'
...     def print_name(self):
...         name = input('Input some name: ')
...         print('self.name', self.name)
...         print('name', name)
...     
>>> ni = no_init()
>>> ni.print_name()
Input some name: Testing
self.name I have no init function
name Testing
>>> ni.name
'I have no init function'

>>> class no_init(object): ... name = 'I have no init function' ... def print_name(self): ... name = input('Input some name: ') ... print('self.name', self.name) ... print('name', name) ... >>> ni = no_init() >>> ni.print_name() Input some name: Testing self.name I have no init function name Testing >>> ni.name 'I have no init function'

As you can see, the name attribute is always "I have no init function" even though there is a " name " inside my print_name function. This is because that particular object is created and destroyed inside that function only. To refer to an attribute of a class from inside the class declaration you need to use self. , whereas outside the class you use the object's instance. So in the above I used ni.name as ni is the instance of the no_init class and name is the attribute I'm looking for.

The following code is identical but uses an init function instead (this is the recommended way to do classes, and it's good to get into the habit of using them):

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python Syntax (Toggle Plain Text)

>>> class yes_init(object):
...     def __init__(self):
...         self.name = 'I have no init function'
...     def print_name(self):
...         name = input('Input some name: ')
...         print('self.name', self.name)
...         print('name', name)
...     
>>> yi = yes_init()
>>> yi.print_name()
Input some name: Testing 2
self.name I have no init function
name Testing 2
>>> yi.name = 'New name'
>>> yi.print_name()
Input some name: Testing 3
self.name New name
name Testing 3
>>>

>>> class yes_init(object): ... def __init__(self): ... self.name = 'I have no init function' ... def print_name(self): ... name = input('Input some name: ') ... print('self.name', self.name) ... print('name', name) ... >>> yi = yes_init() >>> yi.print_name() Input some name: Testing 2 self.name I have no init function name Testing 2 >>> yi.name = 'New name' >>> yi.print_name() Input some name: Testing 3 self.name New name name Testing 3 >>>

You see inside the init function I immediately started referring to the attribute name as self.name . This makes it easier for a casual reader of code to identify which name is which.

HTH

Originally Posted by vegaseat

Since Employee is inherited by Calc it also inherits method get_details(). So use this method with the instance of Calc. You need to keep track of the instance with 'self' ...

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python Syntax (Toggle Plain Text)

class Employee(object):
    name = ' '
    def get_details(self):
        self.name = input('Enter the employee name ')
        print("In super class-->", self.name)
 
 
class Calc(Employee):
    def pr(self):
        print("In sub class==>", self.name)
 
 
if __name__=='__main__':
    y = Calc()
    y.get_details()
    y.pr()
    # create another instance
    y2 = Calc()
    y2.get_details()
    y2.pr()

class Employee(object): name = ' ' def get_details(self): self.name = input('Enter the employee name ') print("In super class-->", self.name) class Calc(Employee): def pr(self): print("In sub class==>", self.name) if __name__=='__main__': y = Calc() y.get_details() y.pr() # create another instance y2 = Calc() y2.get_details() y2.pr()

Note: by convention class names are capitalized so you can trace them easier.