[Tutor] set/getattr and inheritance

[Run-Sun Pan]

Hi all,

I am using the __setattr__ and __getattr__ pair
to access variables of my class:

#-------------------------
class c_template():        
  myAddr = 'blahblahblah'
  
class c_myclass(c_template):
  def __init__(self):
    self.__dict__['vars']={}
    self.vars['myName']='pan'
    
  def __setattr__(self,name,value):
    if not self.vars.has_key(name): raise AttributeError
    self.vars[name]=value
    
  def __getattr__(self,name):
    if not self.vars.has_key(name): raise AttributeError
    return self.vars[name]

mc = c_myclass()
mc.myName='panpan'
mc.myAddr='blah' # trying to use the var of ancestor c_template
#---------------------------

The last line of code raises an AttributeError. It's 
quite obvious that this .myAddr is not in the "vars" 
variable list of the current class (c_myclass), thus
an error occurs. 

I can overcome this by redefining the c_myclass as:

 class c_myclass(c_template):
   def __init__(self):
     myName='pan'
    
or simply:

  class c_myclass(c_template):
     myName='pan'
 
which means, bypassing the usage of __setattr__, 
__getattr__ pairs. But then I can't utilize their
functions to check the input values before they
are assigned / obtained. 

Is there anyway to use these setattr/getattr pair
yet still be able to access ancestor's variables ?

thx in advance.

pan