How can I ignore ValueError when I try to remove an element from a list?
A good and thread-safe way to do this is to just try it and ignore the exception:
try: a.remove(10)except ValueError: pass # do nothing!
I'd personally consider using a set instead of a list as long as the order of your elements isn't necessarily important. Then you can use the discard method:
>>> S = set(range(10))>>> Sset([0, 1, 2, 3, 4, 5, 6, 7, 8, 9])>>> S.remove(10)Traceback (most recent call last): File "<stdin>", line 1, in <module>KeyError: 10>>> S.discard(10)>>> Sset([0, 1, 2, 3, 4, 5, 6, 7, 8, 9])
As an alternative to ignoring the ValueError
try: a.remove(10)except ValueError: pass # do nothing!I think the following is a little more straightforward and readable:
if 10 in a: a.remove(10)