Python ternary operator

Question

How can I do something like var foo = (test) ? "True" : "False"; in Python (specifically 2.7)?

score 94 · Accepted Answer · answered Nov 05 '10 at 04:52

94

PEP 308 adds a ternary operator:

foo = "True" if test else "False"

It's been implemented since Python 2.5

answered Nov 05 '10 at 04:52

Brian McKenna

Wow. You beat me by 12 seconds and have character for character the same answer I did. – Jamie Wong Nov 05 '10 at 04:53
Thanks, I will accept this answer as soon as SO allows it :) – cynicaljoy Nov 05 '10 at 04:54

score -1 · Answer 2 · answered Nov 05 '10 at 09:24

-1

This one looks a bit more like original ternary:

foo=a and b or c

answered Nov 05 '10 at 09:24

Frost.baka

`f = a or b or c` works the same as in javascript (it returns the first truthy value). – Hakim Dec 31 '13 at 18:40
6

-1 Beware, there is a case where this does not work: if the condition `a` is True and `b` is any false value, such as False, 0, None, [], {} and so on, then the result is `c`, which is wrong (it should be `b`). For example, (True and [] or [1,2,3]) is equal to [1,2,3], while ([] if True else [1, 2, 3]) is equal to [], as it should be. I recommend sticking to the official ternary operator. – MiniQuark Mar 03 '17 at 15:03

2 Answers2