[EMAIL PROTECTED] wrote: >> What is your (concrete) use case, by the way? > > > > I try to make it simple (there is almost 25000 lines of code...) > I have a sheet with geometrical objects (points, lines, polygons, > etc.) > The sheet have an object manager. > > So, to simplify : > >>>> sheet.objects.A = Point(0, 0) >>>> sheet.objects.B = Point(0, 2) >>>> sheet.objects.C = Middle(A, B) > > Then we have : > >>>> sheet.objects.A == sheet.objects.B > True > > since have and B have the same coordinates. > But of course A and B objects are not same python objects. > In certain cases, some geometrical objects are automatically > referenced in the sheet, without being defined by the user. > (Edges for polygons, for example...) > But they must not be referenced twice. So if the edge of the polygon > is already referenced (because the polygon uses an already referenced > object for its construction...), it must not be referenced again. > However, if there is an object, which accidentally have the same > coordinates, it must be referenced with a different name. > > So, I use something like this in 'sheet.objects.__setattr__(self, > name, value)': > if type(value) == Polygon: > for edge in value.edges: > if edge is_in sheet.objects.__dict__.itervalues(): > object.__setattr__(self, self.__new_name(), edge) > > Ok, I suppose it's confused, but it's difficult to sum up. ;-)
I won't pretend I understand ;) If you make Point immutable you might be able to drop the "must not be referenced twice" requirement. Peter -- http://mail.python.org/mailman/listinfo/python-list
