Question

while i’m interating a list, how can i get the id of the current item to reference it to list methods?

xl = [1,2,3] # initial list
yl = [3,2]   # list used to remove items from initial list

for x in xl[:]:
    for y in yl:
        if x == y:
            xl.pop(x) # problem
            break
        print x, y
print xl

in the simple example, i want to loop through the 2 lists, and when i find a similar item, remove it from list 1.

What should i use instead of X in the line commented with “#problem”?

PS: Note it’s a copy i’m iterating from.

Answer 1

The general way to do this is with enumerate.

for idx, item in enumerate(iterable):
  pass

But for your use case, this is not very pythonic way to do what you seem to be trying. Iterating over a list and modifying it at the same time should be avoided. Just use a list comprehension:

xl = [item for item in xl if item not in yl]