Is there a dunder for this? Perhaps something along the lines of: (updated)
class Tree:
def __init__(self, item_or_tree):
self._setto(item_or_tree)
def __assign__(self, val):
self._setto(item_or_tree)
def __setitem__(self, which, to_what):
## I would like this to call __assign__ on the Tree object at _tree[which]
to_what._tree[which] = to_what
def __getitem__(self, which):
return self._tree[which]
def __len__(self): return len(self._tree)
def __eq__(self, other):
if isinstance(other, Tree):
if other._is_tree:
return (self._item == other._item) and (self._tree == other._tree)
else:
return self._item == other._item
else: return self._item == other
def _setto(self, item_or_tree):
if isinstance(item_or_tree, Tree):
self._set_from_Tree(item_or_tree)
elif isinstance(item_or_tree, dict):
self._set_from_dict(item_or_tree)
else:
self._set_from_other(item_or_type)
def _set_from_Tree(self, other_Tree):
self._tree = other_Tree[:]
self._item = other_Tree
self._is_tree = other_Tree._is_tree
def _set_from_dict(self, the_dict):
self._is_tree = True
self._item = None
self._tree = {}
for key, val in the_dict.items():
self._tree[key] = Tree(val)
def _set_from_other(self, other):
self._is_tree = False
self._tree = None
self._item = other
class TreeModel(Tree, QAbstractItemModel):
...
## a whole bunch of required overrides
## etc
...
What I'm trying to do is implement a generalized tree structure that acts as intuitively (to me) as possible and also seamlessly integrates with PyQt5's Model-View-Delegate architecture.
I want to be able to set the incoming item_or_tree to either the item or tree. So I'm looking to overload the function that's called when the = operator is used on the item.
PyQt has this item based architecture in which a QAbstractItemModel is overridden. This is (I guess) supposed to return / accept QModelIndex objects. These are trees of tables (2D arrays).
So I'm creating a single tree structure that can contain itself, deal with the 2 opposing indexing paradigms, and plays nice with Python and everything else.
