[Tutor] debugging classes with a __setattr__ method

[Lloyd Kvam]

I have a class for processing DataBase records that keeps a dictionary of the
actual field values from the database in a separate dictionary from the
Class's __dict__ dictionary.  When I try to step through the program using the
debugger,  I can no longer step into the called methods.  Deleting the
__setattr__ method restores normal debugging capabilities.

Is this a normal side effect on the debugger?  Very little of the code depends
on the __setattr__ method, so I can remove it, debug and then put it back.
However, there may be a better way.  Any suggestions?

class Record:
	def __getattr__(self, key):
		""" This is called if the object lacks the attribute.
			If the key is not found, it raises an error in the
			same way that the attribute access would were no
			__getattr__ method present.
		"""
		try:
			return self._record[key]
		except:
			raise AttributeError, "%s not in _record dictionary" % (key)

	def __setattr__(self, key, value):
		if hasattr(self, "_record") and self._record.has_key(key):
			self._record[key] = value
		else:
			self.__dict__[key] = value

	def __delattr__(self, key):
		if hasattr(self, "_record") and self._record.has_key(key):
			raise AttributeError, "Must not delete record attributes.  %s in _record." % (key)
		elif self.__dict__.has_key(key):
			del self.__dict__[key]
		else:
			raise AttributeError, "delete non-existing instance attribute: %s" % (key)


-- 
Lloyd Kvam
Venix Corp.
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