delete items from a set while iterating over it

Question

I have a set myset, and I have a function which iterates over it to perform some operation on its items and this operation ultimately deletes the item from the set.

Obviously, I cannot do it while still iterating over the original set. I can, however, do this:

mylist = list(myset) for item in mylist:     # do sth 

Is there any better way?

Answer 1

First, using a set, as Zero Piraeus told us, you can

myset = set([3,4,5,6,2]) while myset:     myset.pop()     print(myset) 

I added a print method giving these outputs

>>>  set([3, 4, 5, 6]) set([4, 5, 6]) set([5, 6]) set([6]) set([]) 

If you want to stick to your choice for a list, I suggest you deep copy the list using a list comprehension, and loop over the copy, while removing items from original list. In my example, I make length of original list decrease at each loop.

l = list(myset) l_copy = [x for x in l] for k in l_copy:     l = l[1:]     print(l) 

gives

>>>  [3, 4, 5, 6] [4, 5, 6] [5, 6] [6] []