[Zope] can't delete most recently added key from a Persistent dictionary

[Roman Milner]

Hello.  I have a problem trying to use the Persistent mixin class. I
have a dictionary attribute that holds configurable fields.  The
fields are added like this:

	def store_new_fields(self, REQUEST):
		f = self.fields
		if hasattr(REQUEST, 'abstract_p'):
			f[string.strip(REQUEST.new_item_name)] = {'type': REQUEST.dtype,
										'abstract_p': REQUEST.abstract_p}
		else:
			f[string.strip(REQUEST.new_item_name)] = {'type': REQUEST.dtype,
										'abstract_p': 0}
		self.fields = f


I then delete items thusly:

	def del_fields(self, the_fields):
		f = self.fields
		if type(the_fields) == type(""):
			del(f[the_fields])
		else:
			for fname in the_fields:
				del(f[fname])
		self.fields = f


This mostly works fine except the most recently added new field can
not be deleted.  The del() call does not raise an error but when I
look at self.fields.keys() after calling del_fields() on the most
recently added field - it still exists.

I'm sure there is something with the persistence stuff that I am
missing.  Any help would be greatly appreciated.


Thanks,
^Roman