[Tutor] Class inheritance: is the kid calling? or the mom ??

[pan at uchicago.edu]

I have a class which needs calling itself in a function:

class Mom(object):                   
   def __init__(self):
       ...
   def oldfunc(self):                 # line [1]
       ...
       self.someAttr = Mom()
       

Now, I make a new class out of it, added some new functions:

class Kid(Mom):
    def __init__(self):
        Mom.__init__(self)
        ...
    def newfunc(self):
        ...

Then:

mom = Mom()
mom.oldfunc()      # this will asign a new Mom() to mom.someAttr
mom.someAttr.oldfunc()    # ok

Now:

kid = Kid()
kid.newfunc()    # ok
kid.oldfunc()    # this will asign Mom() to kid.someAttr
kid.someAttr.oldfunc()   # ok

kid.someAttr.newfunc()   # not ok ... because kid.someAttr is a Mom,
                         # which doesn't have newfunc().

To make this works, the oldfunc() is recoded as:

class Mom(object):                   
   def __init__(self):
       ...
   def oldfunc(self):                 # line [1]
       ...
       self.someAttr = self.copy()    # line [2] (copy() is pre-defined)


But this slows down the operation by ~ 10 fold.

Is there anyway that a class method can know who is calling it ---
the kid or the mom ? If yes, then we can do :

class Mom(object):                   
   def __init__(self):
       ...
   def oldfunc(self):               # line [1]
       ...
      if called_by_Mom:
          self.someAttr = Mom ()    # line [3] 
      else:  
          self.someAttr = Kid()     # line [4]


or even better, in generalized manner:

class Mom(object):                   
   def __init__(self):
       ...
   def oldfunc(self):                        # line [1]
       ...
       self.someAttr = any_class_that_is_calling_me()    # line [5] 


Is this possible ????

thx.

pan