On Apr 24, 4:04 am, Piet van Oostrum <p...@cs.uu.nl> wrote: > >>>>> dasacc22 <dasac...@gmail.com> (d) wrote: > >d> Ah thank you for clarifying, I did confuse instance and class > >d> attributes from creating the list in the class def. I actually just > >d> spiffed up that class to represent a portion of a much larger class > >d> that needs getter and setter for children. Doing as you said fixed my > >d> problem, heres the code as reference for w/e > >d> class Widget(object): > >d> _children = None > >d> _parent = None > > You still have them as class variables here. Now they are only used as > defaults because you assign to them in the instances so the instance > variables will be created then. But I think it is still confusing to > have these class variables here that you never use as such. Maybe this > is some leftover from Java experience where you do declare instance > variables at the class level? > > >d> def __init__(self, parent=None): > >d> self.children = [] > >d> self.parent = parent > >d> @property > >d> def children(self): > >d> return self._children > >d> @children.setter > >d> def children(self, obj): > >d> self._children = obj > > What is the added value of using a property for the children attribute? > Why not just use an instance variable directly? Also a Java inheritance? > > -- > Piet van Oostrum <p...@cs.uu.nl> > URL:http://pietvanoostrum.com[PGP 8DAE142BE17999C4] > Private email: p...@vanoostrum.org
Hi, yes, you are right, this is from previous experience, and thank you for bringing this out. It would be better suited to move those class variables to a comment to stay comfortable perhaps or eliminate them altogether. The property method of parent and children actually calls a _set_as_parent() and _set_as_child() method after setting the private variable to pack the object for display purposes so that children can be detached from the parent (becoming its own parent) as a gui event. -- http://mail.python.org/mailman/listinfo/python-list
