[Tutor] calling a superclass method after overriding it

[Dave Angel]

Serdar Tumgoren wrote:
>>   def add_name(self):
>>       try:
>>           self.name = SPECIALIZED_SQLcall_for_child()
>>       except SpecialSQLError:
>>           #default to the superclass's add_name method
>>           super(Child, self).add_name()
>>
>>     
> That certainly is a lot easier to read. So if I were to go that route,
> would my "SPECIALIZED_SQLCall_for_child()"  function (I've slightly
> renamed it) have to resemble something like below?:
>
> def SpecialSQLcall_for_child():
>    result = execute some sql_for_special_case()
>     if type(result) != str:
>         raise SpecialSQLError
>     else:
>         return result
>
>   
Exactly.  The whole point of forgiveness/permission is to be able to 
propagate the error without having other code in the path affected by 
it.  So if you return at all, return a real value.  (Raise isn't exactly 
returning, the way I see it, since the flow of control goes elsewhere)

BTW, it's possible that "execute_some_sql...()" might itself be raising 
the exception.  In this case, we might make this call even simpler;  it 
needn't even know anything about the exception.

DaveA