IndexError: Pop from Empty List

Why This Happens

list.pop() removes and returns the last element, but fails on empty lists. This commonly occurs when using a list as a stack or queue without checking if it is empty first.

The Problem

stack = []
item = stack.pop()

The Fix

stack = []
if stack:
    item = stack.pop()
else:
    item = None

Step-by-Step Fix

1. 1

   Check if empty

   Use 'if my_list:' before calling pop().

2. 2

   Use try/except

   Wrap in try/except IndexError.

3. 3

   Use collections.deque

   deque has popleft() for queue behavior and handles empty cases similarly.