weakref list in python

Question

I\'m in need of a list of weak references that deletes items when they die. Currently the only way I have of doing this is to keep flushing the list (removing dead references ma

Answer 1

How do you plan on using B? The only thing I ever do with the weakref list I built is iterate over it, so its implementation is simple:

import weakref

class WeakRefList(object):
    "weakref psuedo list"
    def __init__(yo):
        yo._items = list()
    def __iter__(yo):
        yo._items = [s for s in yo._items if s() is not None]
        return (s() for s in yo._items if s() is not None)
    def __len__(yo):
        yo._items = [s for s in yo._items if s() is not None]
        return len(yo._items)
    def append(yo, new_item):
        yo._items.append(weakref.ref(new_item))
        yo._items = [s for s in yo._items if s() is not None]