Python 3 if-else short-hand command syntax error

Question

Python 3 is showing syntax error whenever I write sys.exit() if condition else return .

Why is this a syntax error? If it can't be fixed is there any way to do the same operation in one line?

Answer 1

return is a statement keyword that can't be used in an x if y else z expression .

Due to sys.exit() never actually returning (since it internally raises a SystemExit exception) and None being the implicit return value if you do return , you could do

return sys.exit() if condition else None

but that's hard to understand and you shouldn't strive to do things in one line for the sake of doing them in one line.

if condition:
    sys.exit()
return

is that much more readable.