How to get first element of list or `None` when list is empty?
Question:
I can do it like this but there has to be better way:
arr = []
if len(arr) > 0:
first_or_None = arr[0]
else:
first_or_None = None
If I just do arr[0] I get IndexError.
Is there something where I can give default argument?
Answers:
I think the example you give is absolutely fine – it is very readable and would not suffer performance issues.
You could use the ternary operator python equivalent, if you really want it to be shorter code:
last_or_none = arr[0] if len(arr) > 0 else None
I can do it like this but there has to be better way:
arr = []
if len(arr) > 0:
first_or_None = arr[0]
else:
first_or_None = None
If I just do arr[0] I get IndexError.
Is there something where I can give default argument?
I think the example you give is absolutely fine – it is very readable and would not suffer performance issues.
You could use the ternary operator python equivalent, if you really want it to be shorter code:
last_or_none = arr[0] if len(arr) > 0 else None