PyGObject: Define a GObject type with a property of the same object type

Platform Language bindings
1

Let us assume I would like to implement a linked list using GObject in python. I would start with this code:

class Item(GObject.Object):
   value = GObject.Property(type=int)
   next_item = GObject.Property(type=Item)

If one tries to run this code snippet then they will see that python complains about “type Item is undefined on line 3”. Essentially, I cannot use the type “Item” in the property until the class “Item” completes its definition.

I could not find a way to have a forward declaration with GObject: Unlike using string in python itself

class Item:
  value: int
  next_item: 'Item'

GObject typing system seems to be not designed to accept strings as a forward declaration of types.

Is this a known deficiency in PyGObject or do I miss something?

2

It’s a known deficiency in PyGObject unfortunately.

The Python class is only defined after the class body, and that’s too late for properties to be added.

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